{"v":2,"generated":"2026-11-01","docs":[{"s":"aav-vectors","t":"AAV vectors","d":"Engineered adeno-associated viruses used to carry therapeutic genes into human cells, the workhorse of in vivo gene therapy and the source of most of its limits.","g":["gene therapy","delivery","viral vectors","immunology","manufacturing","rare disease"],"b":"AAV vectors are gene-delivery vehicles built from adeno-associated virus, a small, non-enveloped parvovirus that infects humans without causing known disease. Nearly every licensed in vivo gene therapy uses one, including treatments for inherited retinal dystrophy, spinal muscular atrophy, and haemophilia. The vector's virtues and its constraints come from the same source: a genome barely large enough to hold one gene, a capsid the immune system recognises, and a payload that mostly sits outside the chromosomes rather than joining them. How it works Wild-type AAV carries about 4.7 kilobases of single-stranded DNA between two inverted terminal repeats, encoding two gene cassettes: rep, for replication, and cap, for the capsid. It cannot complete its own life cycle without a helper virus such as adenovirus or herpes simplex, which is why it was first noticed in 1965 as a contaminant in adenovirus preparations rather than as a pathogen in its own right. To make a vector, everything between the terminal repeats is deleted and replaced with the therapeutic cassette: a promoter, the gene, a polyadenylation signal. The rep and cap functions are supplied separately during manufacturing, so the resulting particle can enter a cell and deliver its cargo but cannot replicate. Once inside, the single-stranded genome is converted to double-stranded DNA and circularises into episomes that per","c":["genetics","bodies"],"k":"technology","x":"established","h":"present","w":1239,"e":"Licensed AAV products treat inherited retinal dystrophy, spinal muscular atrophy and haemophilia in people; the same clinical record shows capsid immunity blocking redosing and fatal liver injury at high systemic doses.","a":"Obtainable only as specific licensed gene therapies given in specialist centres, at one-time list prices in the millions of dollars; patients with pre-existing anti-capsid antibodies are screened out.","r":"context","n":36},{"s":"accelerating-change","t":"Accelerating change","d":"The claim that technological capability grows exponentially or faster, so that the rate of change itself increases over historical time.","g":["forecasting","moore's law","exponential","technology","economics","singularity"],"b":"Accelerating change is the claim that technological capability improves at an increasing rate, so that intervals between comparable advances shorten over time. In its strong form it treats acceleration as a property of technological evolution as such, extrapolable across domains and forward in time. That strong form drives most long-horizon forecasting in this wiki's subject matter, and it is the weakest link in most of that forecasting. The claim Three distinct assertions travel under this heading, and conflating them causes most of the confusion. The descriptive claim is that particular technical metrics have followed exponential curves over decades. This is true of several and false of many. The general claim is that acceleration is a feature of technology as a whole, because each advance provides tools for the next. Ray kurzweil's law of accelerating returns is the best-known version: evolutionary processes build on their own products, so the returns (speed, capability, cost-effectiveness) grow exponentially, and the exponent itself grows. The predictive claim is that these curves can be extrapolated to date future capabilities, including Artificial general intelligence, Whole brain emulation or Longevity escape velocity. This is the contested step, and the descriptive claim does not entail it. Origins Henry Adams noticed the pattern early in the twentieth century, plotting","c":["foundations"],"k":"concept","x":"contested","h":"present","w":1420,"n":11},{"s":"access-and-inequality","t":"Access and inequality","d":"The problem of who can obtain expensive biomedical interventions, and whether biotechnology will convert economic inequality into biological inequality.","g":["justice","pricing","policy","gene therapy","global health","equity"],"b":"Access and inequality names the question of who actually receives a biomedical intervention once it works, and the associated worry that technologies capable of altering bodies and minds will translate existing economic stratification into biological stratification. The concern is old in the literature and recent in practice: until the 2010s no medicine cost enough to make it acute. As of 2026 several licensed therapies are priced above two million dollars per patient. The mismatch between where the diseases are and where the treatments are delivered is the central unsolved problem of the genetic-medicine era. The arithmetic of a one-time cure Conventional pharmaceutical pricing spreads cost over years of dosing. A cure delivered once has to recover its development cost in a single transaction, so the manufacturer's incentive is to price it against the lifetime cost of the disease it displaces rather than against the cost of goods. That logic produced the current price ladder. Onasemnogene abeparvovec for spinal muscular atrophy launched in the US in 2019 at roughly $2.1 million, etranacogene dezaparvovec for haemophilia B at roughly $3.5 million in 2022, and atidarsagene autotemcel for metachromatic leukodystrophy at roughly $4.25 million in 2024, the highest list price ever set for a medicine. Casgevy and a competing lentiviral product for sickle cell disease were approved in","c":["society"],"k":"concept","x":"established","h":"present","w":1730,"n":78},{"s":"aging-biomarkers","t":"Aging biomarkers","d":"Measurable indicators meant to track the rate or extent of biological aging, sought as surrogate endpoints so that anti-aging trials can read out in years rather than decades.","g":["biomarkers","aging","clinical trials","regulation","measurement"],"b":"Aging biomarkers are measurable quantities intended to indicate how far or how fast a person is aging, independent of the calendar. The field wants them for a practical reason. Without one, a trial testing whether a drug slows aging must wait for participants to become ill or die, which takes decades and very large numbers of people; a validated biomarker would shorten that to a few years. None has been accepted for the purpose. Why the field needs one The Geroscience hypothesis holds that slowing aging would delay many chronic diseases at once, and testing it requires an endpoint. Lifespan is unambiguous but unusable in humans. The incidence of a single disease brings back the disease-by-disease framing the hypothesis was built to escape. The TAME design adopts a compromise, a composite of several age-related diseases plus death, and it still needs thousands of participants followed over years. A surrogate biomarker would change the economics. With a six-month readout, sponsors could run dose-ranging studies, compare candidate compounds and abandon failures early, as drug developers do in every field that has a surrogate. Its absence is a substantial part of the reason so few geroprotector candidates have entered serious human testing despite a large animal literature. What counts as a biomarker of aging The criteria most often cited descend from work sponsored by the American","c":["longevity"],"k":"concept","x":"emerging","h":"late 2020s","w":1290,"n":69},{"s":"ai-drug-discovery","t":"AI drug discovery","d":"The use of machine learning to select drug targets, generate candidate molecules and predict failure, so far demonstrably faster at making compounds than at making medicines.","g":["machine learning","drug development","generative chemistry","target discovery","clinical trials","pharmacology"],"b":"AI drug discovery is the application of machine learning to the early stages of pharmaceutical research: choosing which protein to drug, generating molecules that might bind it, predicting which of those will be soluble, selective and non-toxic, and planning routes to synthesize them. The chemistry claims are the better supported ones: software now proposes synthesizable, potent-looking compounds against a defined target at a speed no medicinal-chemistry team matches by hand, though how much of that speed the models themselves explain is disputed. The clinical claims are not settled. As of August 2026 several AI-derived candidates have entered phase 1 and phase 2 trials, the first small molecule among them has begun phase 3, and none has been approved; the one positive phase 3 readout claimed for the field comes from a therapy in which the algorithmic step is antigen selection rather than molecule design. What the models actually do The label bundles at least five tasks that succeed and fail independently. Target selection ranks proteins whose modulation might change a disease, using expression data, genetic association studies, knowledge graphs assembled from the literature, and increasingly language models reading that literature directly. The most consequential public case is BenevolentAI's identification of baricitinib, an approved rheumatoid arthritis drug, as a plausible ","c":["foundations","longevity"],"k":"technology","x":"emerging","h":"late 2020s","w":2482,"e":"AI-derived small molecules have reached phase 1 and 2 trials, with a first phase 3 begun in 2026; sponsors of an mRNA therapy built on algorithm-selected neoantigens report a phase 3 in melanoma met its endpoints, and no drug from either route is approved.","a":"Platforms are proprietary to pharmaceutical companies or licensed to them, and some models and datasets are public; no molecule designed this way is available outside a trial, though AI-suggested uses of approved drugs are.","r":"context","n":12},{"s":"ai-protein-design","t":"AI protein design","d":"Machine-learning systems that predict what shape a protein sequence folds into and that generate new proteins with no natural counterpart.","g":["machine learning","protein design","structural biology","alphafold","biosecurity","drug discovery"],"b":"AI protein design covers two distinct uses of machine learning on proteins: predicting the three-dimensional structure a given amino acid sequence folds into, and generating new sequences that fold into a shape chosen in advance. The first was largely solved for single chains between 2018 and 2021, mostly by DeepMind's AlphaFold. The second is being solved unevenly, by generative models from David Baker's laboratory and others, and it is the half that produces molecules which have never existed. AlphaFold predicts; it does not design. Two problems, not one Prediction rests on Christian Anfinsen's finding that a small protein's sequence contains the information needed to specify its folded structure. Reading that information out resisted fifty years of physics-based attack. From 1994 the field measured its progress through CASP, a biennial blind assessment run by John Moult in which groups predict structures already solved experimentally but not yet published. AlphaFold2's entry at CASP14 in 2020 returned a median score above 90 on the assessment's main accuracy metric, close to the level at which two experimental determinations of the same protein differ from each other. Design is the inverse problem, with no Anfinsen result to guarantee it is solvable. The Baker laboratory's Top7, reported in 2003, was the first protein designed to a fold not found in nature whose crystal stru","c":["genetics","foundations"],"k":"technology","x":"emerging","h":"present","w":1631,"e":"A computationally designed nanoparticle scaffold is a component of a COVID-19 vaccine approved for use in people in South Korea, and a designed cytokine mimic reached early-phase human trials; no de novo designed protein is approved as a therapeutic.","a":"Most prediction and design code is open source and the AlphaFold structure database is public, so the models are free to run; the gene synthesis and wet-lab testing that turn a design into a molecule are not.","r":"context","n":22},{"s":"alcor","t":"Alcor Life Extension Foundation","d":"A United States cryonics organization, founded in 1972, that preserves legally dead members at cryogenic temperatures under a trust structure meant to fund storage indefinitely.","g":["cryonics","cryopreservation","nonprofit","death","trusts","vitrification"],"b":"Alcor Life Extension Foundation is a nonprofit organization in Scottsdale, Arizona that performs and maintains human cryopreservation. Founded in California in 1972, it is among the largest such organizations by number of patients in storage, and it has done more than most to formalize the practice with standby teams, vitrification protocols and a segregated trust intended to fund liquid nitrogen indefinitely. It makes no claim that revival is currently possible, and its own literature describes the arrangement as a bet. Overview Alcor's work is administrative as much as technical. Preservation must begin immediately after a physician pronounces death, which requires knowing when a member is dying, having people and equipment in place, and holding a legal instrument that survives family objection. The organization's procedures are built around that timing problem, and its documented failures have generally been failures of logistics rather than of cryobiology. The same rule cuts the other way. Nothing may be done before pronouncement, which guarantees an interval of warm ischemia and rules out preserving a member whose brain is being destroyed by a progressive disease while they remain legally alive. That constraint sits awkwardly beside assisted-dying law and has been challenged unsuccessfully in court. Members sign a contract and fund it, most commonly by naming Alcor as bene","c":["organizations","longevity"],"k":"organization","x":"established","h":"indefinite","w":1377,"n":9},{"s":"altos-labs","t":"Altos Labs","d":"A biotechnology company launched in 2022 with about three billion dollars in committed funding to develop cellular rejuvenation programming as a medicine.","g":["reprogramming","rejuvenation","biotech","aging","venture funding","cell biology"],"b":"Altos Labs is a privately held biotechnology company, launched publicly in January 2022 with roughly three billion dollars in committed capital, that aims to turn cellular reprogramming into a treatment for age-related disease. It is among the largest single financial commitments made to rejuvenation biology, and as of 2026 it has published research but has not publicly named a clinical candidate. Its existence is the clearest evidence that reprogramming has moved from academic curiosity to industrial programme. Whether reprogramming can be made into a drug remains open. Overview The company's stated goal is \"cellular rejuvenation programming\": restoring the function of aged or damaged cells by resetting their epigenetic state, without converting them into a different cell type and without producing tumours. Its scientific premise is that aging involves a substantial component of reversible epigenetic change rather than only irreversible damage, and that the Yamanaka factors provide a handle on it. Altos was assembled unusually. Rather than licensing a technology and building a pipeline, it recruited senior academic laboratories more or less intact, paid salaries reported to be several times academic norms, and gave principal investigators freedom to publish. The structure resembles a privately funded research institute more than a conventional startup. The company has said thi","c":["organizations","longevity"],"k":"organization","x":"emerging","h":"2030s","w":1208,"n":19},{"s":"alzheimers-disease","t":"Alzheimer's disease","d":"The neurodegenerative disease responsible for most dementia, driven above all by age, and the disease that decides whether added years of life come with a working mind.","g":["dementia","neurodegeneration","amyloid","tau","aging","brain","apoe"],"b":"Alzheimer's disease is the neurodegenerative disease behind 60-70% of dementia: a progressive loss of memory, then language, judgement, and finally the capacity to live unassisted, marked in the brain by extracellular plaques of amyloid-β and tangles of tau protein inside neurons. Its overwhelming risk factor is age. For the arguments this wiki tracks it is the counterpart of Cancer: cancer sets the ceiling on how long a body lasts, and Alzheimer's asks whether the mind lasts as long as the body does. An age-related disease Dementia prevalence roughly doubles with every five years of age past 65, making it an old-age disease in the demographic sense cancer is. The World Health Organization estimates that 57 million people were living with dementia in 2021, with nearly 10 million new cases a year, and counts it the seventh leading cause of death worldwide; the Alzheimer's Association estimates 7.2 million Americans aged 65 and over have Alzheimer's dementia in 2025, with a projected near-doubling by 2060 absent better treatment or prevention. The growth is driven by population aging; age-specific risk has declined in several high-income countries. Why this matters here Eliminating dementia would add little life expectancy, because its victims are old and die of something else soon after; what it would remove is a large share of late-life disability. That makes Alzheimer's the sh","c":["longevity","foundations"],"k":"concept","x":"established","h":"present","w":1701,"e":"Two anti-amyloid antibodies slowed cognitive decline by roughly a quarter to a third over 18 months in phase 3 trials; no treatment has stopped or reversed the disease in people.","n":8},{"s":"anders-sandberg","t":"Anders Sandberg","d":"Swedish computational neuroscientist and futures researcher who co-wrote the whole brain emulation roadmap and works on the physical limits of long-term civilization.","g":["whole brain emulation","existential risk","forecasting","computational neuroscience","transhumanism"],"b":"Anders Sandberg is a Swedish computational neuroscientist and futures researcher whose work consists largely of putting numbers on questions that are usually discussed without them: how much compute a brain emulation would need, how long it would take to colonize a galaxy, how much confidence a risk estimate can carry when the model itself might be wrong. He co-authored the standard technical roadmap for Whole brain emulation and spent nearly two decades at Oxford's Future of Humanity Institute. Career Sandberg's doctorate, completed at Stockholm University in 2002, was on attractor neural network models of memory, the mathematics of how a network of units settles into stable states that behave like stored patterns. That background explains his position on emulation. He approaches the question as a modeller who has built neural systems rather than as a philosopher arguing from the outside. He chaired the Swedish transhumanist association during the 1990s and co-founded a Stockholm think tank before joining the Future of Humanity Institute in 2006. There he worked with Nick bostrom, Toby Ord, Eric drexler and others until the institute closed in 2024, after which he moved to the Institute for Futures Studies in Stockholm. He is a prolific public communicator, and much of his output appears as estimates in blog posts, technical reports and talks rather than as conventional papers","c":["people","minds"],"k":"person","x":"established","h":"present","w":1054,"n":9},{"s":"artificial-blood","t":"Artificial blood","d":"Engineered substitutes for the oxygen-carrying function of blood, including haemoglobin carriers, perfluorocarbon emulsions and cultured red cells, none in general clinical use.","g":["transfusion","oxygen carriers","haemoglobin","trauma","cell culture","clinical trials"],"b":"Artificial blood refers to manufactured substitutes for the oxygen-carrying function of red cells. The term is misleading, because no product replaces blood. Blood carries oxygen and carbon dioxide, clots, transports immune cells, buffers pH, distributes hormones and regulates temperature. Every substitute developed so far addresses only oxygen transport, and is more accurately called an oxygen therapeutic. Four decades of development have produced one product approved and withdrawn in the United States, several approved in other jurisdictions or for veterinary use, a large trial record of harm, and a recent shift toward growing real red cells in culture instead. What a substitute has to do Donated red cells set a demanding benchmark. They circulate for months, release oxygen in response to local acidity and carbon dioxide, do not leak their contents into tissue, and are cleared by an orderly process when worn out. A substitute must match enough of that to be useful without triggering the vascular and oxidative injury that free haemoglobin causes, and it must do so at a price and shelf life that justify displacing a donation system that already works in wealthy countries. The one property no candidate has ever attempted is the rest of blood's job: clotting, immunity and the transport of everything that is not oxygen. Whole blood, and the Organ shortage-like logistics of collect","c":["bodies","nanomedicine"],"k":"technology","x":"experimental","h":"2030s","w":1507,"e":"Trials of cell-free haemoglobin carriers in people showed excess mortality and myocardial infarction across sixteen studies; the human data on cultured red cells are small tagged-volume transfusions in volunteers.","a":"No product is licensed in the United States for general transfusion; a polymerized bovine carrier is licensed in South Africa and available in the US only under expanded access, and cultured red cells exist only inside trials.","r":"reversible","n":11},{"s":"artificial-general-intelligence","t":"Artificial general intelligence","d":"A hypothetical artificial system matching or exceeding competent human performance across essentially all cognitive tasks rather than in narrow domains.","g":["artificial intelligence","agi","forecasting","benchmarks","machine learning","risk"],"b":"Artificial general intelligence is a hypothetical artificial system whose competence spans essentially the full range of cognitive tasks humans perform, rather than being confined to a domain it was built for. The term functions mainly by contrast with narrow AI: a chess engine, a protein-structure predictor and a fraud-detection model are each superhuman within their scope and useless outside it. Whether any existing system has begun to cross that boundary is one of the most consequential open disputes in science, and it is unresolved partly because the boundary has never been defined in a way that would settle it. Defining the target There is no accepted definition. Legg and Hutter, surveying the problem, assembled more than seventy published definitions of intelligence and extracted a common core: intelligence measures an agent's ability to achieve goals in a wide range of environments. That formulation is precise enough to be formalised and too abstract to adjudicate any actual system. Working definitions split into three families. Task-based definitions specify jobs a system must do. The Turing test is the ancestor; modern versions substitute economically valuable work or a benchmark suite. Capability-based definitions specify cognitive functions such as transfer learning, long-horizon planning, or acquiring new skills without retraining. Autonomy-based definitions require","c":["foundations","minds"],"k":"concept","x":"contested","h":"indefinite","w":1590,"n":27},{"s":"artificial-heart","t":"Artificial heart","d":"Mechanical devices that take over some or all of the heart's pumping function, from routine ventricular assist pumps to total replacements used mainly as a bridge to transplant.","g":["circulatory support","implants","heart failure","transplantation","medical devices","haemocompatibility"],"b":"Artificial heart is the general term for a mechanical pump that takes over the circulatory work of a failing heart. The category divides into ventricular assist devices, which work alongside a heart left in place, and total artificial hearts, which replace the ventricles entirely after the native heart is excised. The first are a routine therapy implanted in thousands of patients a year; the second remain rare, used mostly to keep a patient alive until a donor organ appears. The engineering history of both is a record of trading one failure mode for another. How it works An adult heart moves roughly five litres a minute against arterial pressure, adjusts that output over a fivefold range in response to demand, and does so for decades without maintenance in a fluid that clots on contact with foreign surfaces. Any replacement has to approximate all four properties. Pulsatile designs copy the heart's method: a flexible chamber compressed by air or a pusher plate, with inflow and outflow valves. They generate physiological pulse pressure and can be volume-matched to the patient. They are also large, contain flexing membranes that fatigue, and require valves that wear. Continuous-flow designs use a rotating impeller. They have one moving part, are far smaller, and have no flexing components to fail. Early axial-flow pumps rested the rotor on mechanical or hydrodynamic bearings; curr","c":["bodies"],"k":"technology","x":"established","h":"present","w":1443,"e":"Randomized trials in adults with advanced heart failure show left ventricular assist devices improve survival, the magnetically levitated pump holding its advantage at five years; total artificial hearts rest on bridge-to-transplant series.","a":"Implanted in specialist cardiac surgery centres in high-income health systems; a durable assist device and its implantation run to hundreds of thousands of dollars, and total artificial hearts are used in tens of patients a year.","r":"difficult","n":9},{"s":"artificial-womb","t":"Artificial womb","d":"A device that sustains fetal development outside a body by perfusing the umbilical circulation while the fetus remains immersed in fluid, tested so far only in animals.","g":["reproduction","ectogenesis","prematurity","neonatology","bioethics","medical devices"],"b":"Artificial womb is the common name for a device that supports a fetus outside a pregnant body by connecting it to an external oxygenator through the umbilical vessels while it remains submerged in a fluid environment. Every system built so far is designed for partial ectogenesis: it takes over from a pregnancy already underway, at the edge of viability, and aims to carry the fetus a few more weeks. No device has gestated a mammal from conception, and none has been used in a human. The difference between continuing a pregnancy and replacing one is the most important fact about the technology, and it is the fact that coverage most often loses. How it works The design problem starts with the fetal lung, which cannot yet do a lung's job. Below roughly 26 weeks of human gestation the alveoli are too few and too thick-walled for gas exchange, and mechanical ventilation of such a lung causes the chronic injury known as bronchopulmonary dysplasia. Conventional neonatal intensive care manages this trade-off; an artificial womb tries to avoid it by never asking the lung to breathe. The current systems differ from an incubator in four ways: - Umbilical cannulation. Blood is drawn from and returned to the umbilical vein and arteries, preserving fetal circulation with its right-to-left shunts through the ductus arteriosus and foramen ovale. Neck or chest cannulation, as used in standard ext","c":["reproduction","bodies"],"k":"technology","x":"experimental","h":"2030s","w":1878,"e":"No human has been supported by a modern system and no trial has enrolled anyone; the results are from preterm lambs, and 1960s perfusion of previable human fetuses produced no survivors.","a":"Nothing to obtain: the systems exist only as research prototypes in a handful of laboratories, and no regulator has authorised a first-in-human trial.","r":"difficult","n":10},{"s":"asilomar-conference","t":"Asilomar Conference on Recombinant DNA","d":"The 1975 meeting at which molecular biologists lifted their own moratorium on recombinant DNA work by agreeing a system of physical and biological containment.","g":["governance","biosafety","recombinant dna","self-regulation","moratorium","history of science"],"b":"The Asilomar Conference on Recombinant DNA was a four-day meeting of about 140 scientists, lawyers, and journalists held in February 1975 at a conference ground on the California coast, convened to decide whether and how experiments splicing DNA between species should resume. Its participants had imposed a voluntary moratorium on themselves the previous year; at Asilomar they lifted it, replacing prohibition with a graded system of laboratory containment. The meeting is invoked, half a century later, as the template for scientific self-governance, including in the debates over Germline editing, and the accuracy of that analogy is itself contested. In February 2025 a summit returned to the same conference grounds for the fiftieth anniversary, and closed by publishing a set of signed entreaties rather than a single agreed framework. Background The techniques arrived quickly. By the early 1970s it was possible to cut DNA at defined sequences with restriction enzymes, join fragments from different organisms, and propagate the result in bacteria. Paul Berg's laboratory at Stanford planned to insert DNA from SV40, a monkey virus that causes tumours in rodents, into a bacteriophage that grows in Escherichia coli, a bacterium that lives in the human gut. A colleague pointed out the obvious hazard, and Berg suspended the experiment. Concern spread through the field rather than into it f","c":["genetics","society"],"k":"event","x":"historical","h":"historical","w":1522,"n":15},{"s":"aubrey-de-grey","t":"Aubrey de Grey","d":"British biogerontologist who proposed the SENS damage-repair framework for rejuvenation and popularized the idea of longevity escape velocity.","g":["aging","sens","biogerontology","life extension","rejuvenation","advocacy"],"b":"Aubrey de Grey is a British biogerontologist who argues that aging should be treated as a finite set of accumulated molecular and cellular lesions that periodic repair can remove, rather than as a metabolic process that medicine must learn to slow. He formalized that position as SENS (Strategies for Engineered Negligible Senescence) and popularized the term Longevity escape velocity. He is the most visible advocate of radical life extension and among the most heavily criticized figures in the field. Overview De Grey's importance is organizational and rhetorical more than experimental. He has run almost no wet-lab research of his own. His primary contribution is a framework, which claims that the damage accumulated during aging falls into a small number of categories, that each category has a conceivable repair strategy, and that the list is complete enough to serve as an engineering specification. Mainstream biogerontology has largely accepted his framing question, whether aging is tractable at all, while rejecting his timelines and much of his confidence. Career De Grey read computer science at Trinity Hall, Cambridge, and spent his early career as a software engineer, including work in artificial-intelligence tooling. His entry into biology came through his marriage to the Cambridge geneticist Adelaide Carpenter and through self-directed reading in the aging literature. In 19","c":["people","longevity"],"k":"person","x":"contested","h":"present","w":1209,"n":13},{"s":"autophagy","t":"Autophagy","d":"The lysosomal pathway by which cells digest their own damaged components, and the process through which most known lifespan-extending interventions appear to act.","g":["aging","autophagy","lysosome","mtor","cell biology","mechanisms"],"b":"Autophagy is the process by which a cell delivers its own cytoplasmic contents (misfolded proteins, damaged organelles, invading bacteria, surplus lipid) to the lysosome for degradation and recycling. It is the bulk arm of protein quality control and the only route by which a cell can dispose of a structure too large for the proteasome. Disabled macroautophagy was added as a separate entry to the Hallmarks of aging in 2023. In invertebrates, interfering with autophagy genes abolishes the lifespan extension produced by most known geroprotective interventions. Three forms Macroautophagy, the form usually meant by the unqualified term, engulfs cargo in a double-membraned vesicle that then fuses with a lysosome. Microautophagy takes up small volumes of cytosol by invaginating the lysosomal membrane directly. Chaperone-mediated autophagy selects individual proteins carrying a KFERQ-like motif: HSC70 recognizes the motif and delivers the protein to the lysosomal receptor LAMP2A, where it is unfolded and translocated directly across the membrane. Only mammals and some other vertebrates have this third form, and it declines steeply with age in rodent liver. Mechanics Macroautophagy begins when the ULK1 kinase complex nucleates an isolation membrane, or phagophore. Lipid reaches the site from ATG9-containing vesicles and from the class III phosphatidylinositol 3-kinase complex built aro","c":["longevity"],"k":"concept","x":"established","h":"present","w":1120,"e":"The pathway itself is established in human cells, but autophagic flux cannot be measured in a living person, and every lifespan result comes from yeast, worms, flies and mice.","n":22},{"s":"base-editing","t":"Base editing","d":"A genome editing method that chemically converts one DNA base into another at a targeted site without cutting both strands of the double helix.","g":["crispr","genome editing","gene therapy","point mutations","biotechnology"],"b":"Base editing converts one DNA letter directly into another at a chosen position, using an enzyme that chemically modifies a base rather than a nuclease that severs the chromosome. It was built to solve a specific weakness of Crispr cas9: most disease-causing mutations are single-letter substitutions, and correcting a single letter with a double-strand break is inefficient and messy. Base editors handle four of the twelve possible substitutions, which covers a large fraction of known pathogenic point mutations but by no means all of them. How it works A base editor is a fusion protein. The targeting half is a catalytically impaired Cas9 that binds DNA under guide-RNA control but cuts at most one strand. The working half is a deaminase, an enzyme that strips an amine group from a base and changes what the cell's polymerases read. Cytosine base editors, described in 2016, use a cytidine deaminase to convert cytosine to uracil. Uracil is read as thymine during replication, so a C•G pair becomes T•A. Because cells actively excise uracil from DNA, the editor also carries a uracil glycosylase inhibitor to block that repair, and nicks the opposite strand so the cell rebuilds it using the edited strand as template. Adenine base editors, described in 2017, had no natural starting enzyme: no known deaminase acts on adenine in DNA. The solution was directed evolution of a bacterial tRNA ad","c":["genetics"],"k":"technology","x":"emerging","h":"late 2020s","w":2126,"e":"All human use is trial-stage or one-off: edited CAR-T cells for one leukaemia patient in 2022, a 35-adult phase 1 liver trial (mean LDL down 62% at the top dose), 31 patients in an ex vivo sickle cell trial, and a bespoke editor given to one infant.","a":"No base-editing therapy is approved anywhere as of November 2026; the only routes are clinical trials and one-off bespoke treatments authorised for a single patient.","r":"irreversible","n":21},{"s":"artificial-neurons","t":"Bio-interfacing artificial neurons","d":"Physical electronic devices that generate neuron-like spikes at biological voltages and timescales so they can exchange signals directly with living nerve cells and tissue.","g":["neuromorphic","memristors","organic electronics","bioelectronics","neural interface","neuroprosthetics"],"b":"Bio-interfacing artificial neurons are electronic devices built to produce spikes resembling a nerve cell's action potential, at voltages, energies and timescales close enough to biology that the device can drive living neurons or be driven by them. They are a proposed building block for Neuroprosthetics that would compute and signal in the nervous system's own format rather than through fixed stimulation pulses. As of October 2026 every demonstration of an artificial neuron coupled to living tissue has been an acute laboratory experiment in cells, brain slices or anaesthetized animals, and no study has reported implanting one in a person. What the term covers \"Artificial neuron\" names three different things, and news coverage regularly blurs them. The oldest is mathematical. The units of a software neural network, descended from the McCulloch-Pitts model of 1943, are weighted sums passed through a nonlinearity. They have no physical form and no electrical contact with anything biological, and they are what the phrase means in machine learning and in debates about Artificial general intelligence. The second is neuromorphic hardware: circuits that emulate spiking neurons physically, mostly to compute more efficiently. Mahowald and Douglas built an analog \"silicon neuron\" in 1991 that reproduced the ion currents behind a nerve impulse in real time. Most neuromorphic hardware sinc","c":["cybernetics"],"k":"technology","x":"experimental","h":"2040s","w":1520,"e":"No human study has been run; every coupling to living tissue has been acute, in mouse brain slices, cultured rat neurons, stem-cell-derived heart cells in a dish, or the vagus nerve of anaesthetized mice.","a":"Nothing to obtain: these are laboratory prototypes with no approved device, no commercial product, and no reported human trial.","r":"difficult","n":2},{"s":"bioconservatism","t":"Bioconservatism","d":"The position that biotechnological modification of human beings should face a strong presumption against it, grounded in dignity, precaution, or the value of the given.","g":["bioethics","philosophy","precaution","human dignity","politics"],"b":"Bioconservatism is the view that deliberate biotechnological alteration of human nature should meet a strong presumption against it, and that some such alterations should be refused outright rather than regulated. The label was coined in transhumanist circles in the early 2000s and is used mostly by opponents of the position; few of the writers it describes adopt it. They share a structure of argument rather than a politics: the burden of justification rests on those who would change the human constitution, not on those who would leave it alone. The core arguments Four distinct arguments run under the heading, and they are often confused with one another. Human dignity. Francis Fukuyama's version holds that equal moral and political rights rest on a complex of species characteristics, which he calls Factor X; it is not reducible to any single trait, and selective modification would fragment it. He named transhumanism the world's most dangerous idea in a 2004 Foreign Policy symposium, on the ground that a society containing beings of engineered and unengineered kinds would have no stable basis for treating its members as equals. The given and the made. Jürgen Habermas argues that a person who learns their dispositions were chosen by another to a design stands in an asymmetric relation to that designer which no naturally born person occupies, and that the symmetry of mutual recog","c":["society"],"k":"concept","x":"established","h":"present","w":1270,"n":20},{"s":"bioethics-of-enhancement","t":"Bioethics of enhancement","d":"The philosophical and policy debate over whether biomedical means may legitimately be used to push human capacities beyond species-typical function.","g":["bioethics","enhancement","philosophy","autonomy","justice","therapy"],"b":"Bioethics of enhancement is the branch of applied ethics that asks whether, and under what conditions, biomedical interventions may be used to raise human capacities above what is typical for the species rather than to restore what disease has taken away. The debate acquired its modern shape around 2000, when genome editing, psychopharmacology, and embryo screening made the question look imminent rather than literary. Two decades later the philosophical positions are well developed and the technologies mostly are not. The result is an unusual literature: a mature argument about capabilities that largely do not yet exist. The line and why it moves The organising distinction is between therapy, which restores or maintains normal function, and enhancement, which improves on it. The line does real institutional work. Insurers reimburse therapy; medical licensing is justified by therapeutic purpose; most genome-editing statutes permit intervention only for \"serious disease\" without defining the term. It also fails under examination. Vaccination adds immunity a person never had rather than restoring a lost function. Contraception disables a working system. Caffeine, corrective lenses, and literacy all improve on the unaided baseline. Growth hormone was approved in the United States in 2003 for idiopathic short stature, a condition defined by height alone rather than by any identified","c":["society","enhancement"],"k":"concept","x":"established","h":"present","w":1765,"n":36},{"s":"biohacking","t":"Biohacking and grinders","d":"The practice of modifying one's own biology outside institutional medicine, ranging from subdermal implants to do-it-yourself gene transfer and open-source medical devices.","g":["diy","implants","self-experimentation","subculture","regulation","citizen science","longevity"],"b":"Biohacking and grinders are, respectively, a loose label for do-it-yourself modification of one's own biology and the name the implant subculture within it uses for itself. The term covers activities with almost nothing in common: inserting a magnet in a fingertip, running an open-source insulin pump, taking a stack of supplements, and injecting an unapproved gene-transfer construct. What unites them is that they deliberately bypass the institutions that normally stand between a person and an intervention on their own body: clinical trials, prescribing physicians and regulators. Strands Grinders implant hardware subdermally. The canonical devices are neodymium magnets in the fingertip, which transduce alternating magnetic fields into a felt vibration and function as a crude added sense of the kind discussed in Sensory augmentation, and glass-encapsulated RFID or NFC transponders in the web of the hand, used to open doors and pair with phones. Amal Graafstra implanted an RFID tag in 2005 and later founded a company supplying implant hardware; several thousand people, concentrated in Sweden and the United States, are thought to carry NFC implants, though no register exists. The word \"grinder\" was borrowed from a comic and adopted by the community around 2010. DIY biology works with molecules rather than hardware. Community laboratories such as Genspace in New York and BioCurious ","c":["enhancement","people"],"k":"concept","x":"contested","h":"present","w":1593,"n":23},{"s":"biohub","t":"Biohub","d":"A nonprofit biomedical research organization founded in 2016 by Priscilla Chan and Mark Zuckerberg, since 2025 the main vehicle of their philanthropy and focused on AI models of cells.","g":["nonprofit","machine learning","single cell","open data","philanthropy","research institutes","infectious disease"],"b":"Biohub, founded in 2016 as the Chan Zuckerberg Biohub, is a nonprofit biomedical research organization created by Priscilla Chan and Mark Zuckerberg to build tools and datasets for biology rather than to develop drugs. It began as a San Francisco institute shared by three Bay Area universities, grew into a network of sites in California, Chicago and New York, and in November 2025 became the couple's primary philanthropic effort with a stated focus on AI models of how cells work. As of October 2026 it anchors what its partners call the largest coordinated commitment yet to generating data for Virtual cell models, on the premise that data is what such models lack. Overview Biohub's stated mission is to \"cure or prevent all disease\", a goal the founders originally framed as a century-long project. Its method has been consistent as its scale changed: fund measurement technology, cell atlases, open software and grants to academic scientists, and publish the results openly. It is not a drug company and has no clinical pipeline, which distinguishes it from technology-funded biology ventures such as Calico and Altos labs and from Ai drug discovery start-ups; in structure it is closer to an independent research institute such as the Buck institute. Chan Zuckerberg Biohub, Inc. is a 501(c)(3) medical research organization; strategic, funding and operational support comes from the Chan Zu","c":["organizations","genetics"],"k":"organization","x":"established","h":"2030s","w":1620,"n":3},{"s":"biological-age","t":"Biological age","d":"An estimate of how far an individual has progressed along the trajectory of age-related decline, expressed in years and compared against their chronological age.","g":["aging","biomarkers","measurement","epigenetics","frailty"],"b":"Biological age is an estimate of where a person sits on the trajectory of age-related functional decline, expressed on the scale of years so that it can be compared with the date on their birth certificate. Two seventy-year-olds can differ enormously in organ function, disease burden and remaining life expectancy, and the concept exists to name that difference. It is used constantly in aging research and has no agreed definition, no gold-standard measurement, and no accepted regulatory status. What the concept is trying to capture Chronological age is the best single predictor of death and of most chronic disease, and it is measured perfectly. The reason to want something else is that it is uninformative about individuals: it cannot distinguish a robust eighty-year-old from a frail one, and it cannot respond to an intervention. A measure that could do both would let researchers test geroprotectors in years rather than decades, which is the practical motivation described under Aging biomarkers. The underlying assumption is that there exists a single latent quantity, the extent of accumulated aging, that many measurable things reflect imperfectly. This assumption is doing a great deal of work and may not be true. If the processes catalogued in the Hallmarks of aging proceed at partly independent rates in different tissues, then a person does not have one biological age but many. ","c":["longevity"],"k":"concept","x":"contested","h":"present","w":1148,"e":"The measures are built and tested in human cohorts, where several predict mortality; none is accepted by a regulator as a surrogate endpoint, and different measures in the same person agree only weakly.","n":48},{"s":"blue-zones","t":"Blue Zones","d":"Five regions claimed to have unusually high concentrations of centenarians, and the lifestyle explanations built on that claim.","g":["aging","demography","diet","public health","epidemiology","centenarians"],"b":"Blue Zones are five regions identified as having exceptional concentrations of people living past 100, together with the lifestyle explanations proposed to account for them. The term originated in demographic fieldwork in Sardinia, and the writer Dan Buettner popularized it in books and television. Since the late 2010s the underlying demographic claim has come under sustained attack, chiefly from work showing that regions with poor birth records produce inflated numbers of very old people. Origins The term comes from the Belgian demographer Michel Poulain and the Italian physician Gianni Pes, who mapped centenarian density in Sardinia and found an unusual cluster in the mountainous interior of Nuoro province. They marked the villages in blue ink, and the phrase stuck. The Sardinian finding stood out less for the absolute number of centenarians than for the sex ratio. The local excess appeared in men, whereas centenarians almost everywhere are overwhelmingly women. Dan Buettner extended the concept in a 2005 National Geographic cover story and a 2008 book, adding Okinawa in Japan, the Nicoya Peninsula in Costa Rica, Ikaria in Greece, and the Seventh-day Adventist community of Loma Linda, California. A 2023 Netflix series brought the framework to a much wider audience. The list has not grown since; Buettner's organization has periodically discussed candidate regions without forma","c":["longevity","society"],"k":"concept","x":"contested","h":"present","w":1450,"e":"The regional claims rest on retrospective age records in places with incomplete birth registration; the best-documented case, the Adventist cohort at Loma Linda, enrolled living people with verified ages.","n":9},{"s":"blueprint-protocol","t":"Blueprint protocol","d":"Bryan Johnson's self-measured anti-aging regimen, begun in 2021, combining diet, exercise, sleep, drugs and experimental therapies, and the company that sells its products.","g":["self-experimentation","n-of-1","biomarkers","supplements","aging","consumer health"],"b":"The Blueprint protocol is the anti-aging regimen that the American entrepreneur Bryan Johnson began in 2021 and has since published, revised and sold in parts: a fixed daily schedule of diet, exercise and sleep, a stack of supplements and prescription drugs, a rotating set of experimental therapies, and continuous measurement of his own body. Johnson calls himself the most biologically measured person ever. No controlled study of the regimen has been run, and the outcomes he reports come from a single, uncontrolled subject who also owns the company that sells its products. Three things called Blueprint The name covers Johnson's personal regimen (originally \"Project Blueprint\"), the free protocol website describing it, and Blueprint, the company selling foods, supplements and personal-care products derived from it. This article covers all three; Johnson's wider \"Don't Die\" movement is covered in his biography. Origins and team Johnson began Project Blueprint in 2021 and co-founded a company of the same name that year. It reached a mass audience through a Bloomberg profile in January 2023, after which coverage put the cost of running it at about $2 million a year. The clinical side was led, as of 2023, by Oliver Zolman, a 29-year-old Cambridge-based doctor with a degree in regenerative medicine, who heads what Fortune described as \"a team of 30-plus doctors and health experts\". Z","c":["longevity","enhancement"],"k":"intervention","x":"contested","h":"present","w":1761,"e":"No controlled or peer-reviewed study of the regimen exists; its evidence is one man's uncontrolled self-measurement, and the only larger dataset, an internal company study, surfaced through leaked documents reporting side effects.","a":"Johnson publishes the regimen free online and Blueprint sells its foods and supplements direct to consumers; the drugs and therapies he reports need prescriptions or clinics, and a 2024 starter subscription cost $333 a month.","r":"context","n":4},{"s":"brain-preservation","t":"Brain preservation","d":"Preserving the structural information in a brain well enough that a future technology could reconstruct its memories, rather than revive the tissue itself.","g":["cryopreservation","connectome","uploading","neuroscience","vitrification","death"],"b":"Brain preservation is the storage of a brain in a state that retains the structural information thought to encode memory and personality, on the assumption that this information, rather than the living tissue, is what would have to survive for a person to be recoverable. It differs from Cryonics in an important respect: the leading method is chemically irreversible and makes no attempt to keep the brain biologically viable. It is a bet on scanning rather than resuscitation, and it is taken up mainly by people who do not expect Longevity escape velocity to arrive in time for them. What is being preserved The premise is that a person's memories and character are physically instantiated in the arrangement of their neurons and synapses, together with molecular details such as receptor composition and synaptic strength. If that arrangement can be frozen in place, literally or chemically, then in principle it can later be read out, whatever the state of the tissue. This shifts the success criterion. Cryonics asks whether damage can be repaired; brain preservation asks whether information has been destroyed. The two lead to different procedures. A method that crosslinks every protein in the brain into an immobile mesh would be catastrophic for revival and excellent for structural preservation, and that is roughly what the field's leading technique does. The trade being made Aldehyde f","c":["minds","longevity"],"k":"technology","x":"experimental","h":"indefinite","w":1270,"e":"Verification is from rabbit and pig brains only; no preserved human brain has been assessed the same way, and no preserved brain of any species has been scanned and shown to yield a working model.","a":"Offered after death by a small number of organizations, at lower cost than liquid-nitrogen cryonics; no provider is known to perform the premortem perfusion the published protocol assumes.","r":"irreversible","n":15},{"s":"brain-to-brain-interface","t":"Brain-to-brain interfaces","d":"Systems that link one nervous system to another by decoding activity from a sender and delivering stimulation to a receiver, so far at rates of a few bits per minute.","g":["bci","telepathy","tms","neural decoding","neurostimulation","bandwidth"],"b":"Brain-to-brain interfaces are systems that connect two nervous systems by decoding a signal from one brain and delivering stimulation to another, without the sender speaking or the receiver listening. Every demonstration so far chains together two established technologies: a Brain computer interface that reads out a single variable, and a neurostimulation device that writes a crude signal in. The arrangement is not telepathic in the sense popular coverage implies. The information rates achieved are the central fact. Across the published human experiments, transmission has amounted to roughly one bit per trial, with trials taking tens of seconds. That works out to a few bits per minute, against roughly forty bits per second for ordinary speech. The transmitted content is a binary code the experimenters defined in advance, not a thought. How it works The sender's side is a decoder. In the non-invasive human experiments the sender looks at one of two flickering targets, which produces a steady-state visual evoked potential at the corresponding frequency in occipital cortex, and scalp electroencephalography can classify that reliably. Alternatively the sender imagines moving a hand, producing a detectable change in sensorimotor rhythms. Either way the output is a single binary decision, the simplest possible case of Neural decoding. The receiver's side is a stimulator, drawn from t","c":["cybernetics","minds"],"k":"technology","x":"experimental","h":"2050s+","w":1067,"e":"All human demonstrations are non-invasive: volunteers have exchanged roughly one bit per trial through scalp EEG and magnetic stimulation, and no healthy person has been implanted for this purpose.","a":"Nothing to obtain: the systems exist only as laboratory setups assembled from research EEG and stimulation equipment, with no product or service on offer.","r":"reversible","n":6},{"s":"brain-computer-interface","t":"Brain–computer interface","d":"A system that measures nervous-system activity, decodes an intention or state from it, and converts that decoded signal into a command for an external device.","g":["bci","neurotechnology","paralysis","neural decoding","implants","assistive technology"],"b":"Brain-computer interface (BCI) is the general term for a system that measures activity in the nervous system, extracts a variable of interest from that activity, and turns it into a command for a computer, a prosthesis, or the person's own muscles. The defining feature, in the standard formulation, is that the command bypasses the ordinary output path of peripheral nerve and muscle. A BCI is therefore useful mainly to people whose ordinary output path is broken, and as of October 2026 every serious clinical result comes from that population: participants with tetraplegia, brainstem stroke, or amyotrophic lateral sclerosis. The field has produced striking demonstrations in a very small number of research participants: a person with no usable movement controlling a robotic arm, another producing fluent synthesized speech from motor-cortex activity alone. The hardware behind them is tethered, requires frequent recalibration, and has not been approved by any regulator for permanent use. The implanted BCI for movement that reached the market in China in March 2026 is far simpler: eight electrodes resting on the dura that let a person with a cervical spinal cord injury close a pneumatic glove. The gap between the laboratory demonstrations and a product lies largely in reliability, longevity, and manufacturing rather than in principle. The signal chain Every BCI has the same four stag","c":["cybernetics","foundations"],"k":"technology","x":"emerging","h":"late 2020s","w":2599,"e":"Implanted arrays have given research participants with paralysis cursor control, robotic-arm use and large-vocabulary speech decoding at up to about 60-80 words per minute; no implanted BCI has been shown to improve any capability in a healthy person.","a":"China approved one epidural BCI for hand grasp after cervical spinal cord injury in March 2026; elsewhere implanted BCIs are trial-only. Consumer EEG headsets are sold freely as wellness devices.","r":"difficult","n":43},{"s":"bryan-johnson","t":"Bryan Johnson","d":"American entrepreneur who founded Braintree and the neurotechnology firm Kernel, then made his own body the subject of Blueprint, a heavily measured and disputed anti-aging regimen.","g":["biohacking","self-experimentation","life extension","biomarkers","neurotechnology","aging"],"b":"Bryan Johnson (born 1977) is an American entrepreneur who made his fortune with the payments company Braintree, founded the brain-measurement company Kernel, and since 2021 has turned his own body into a heavily monitored anti-aging experiment called Blueprint, which he also sells as a consumer brand. Under the slogan \"Don't Die\" he has become the best-known practitioner of longevity Biohacking. Many aging researchers dispute his claims, chiefly because one uncontrolled subject following dozens of simultaneous interventions cannot show that any of them works. Overview Johnson matters to this field as a public example rather than as a scientist. Trained in business rather than biology, he publishes results as posts and videos, not papers. His project combines three things normally kept apart: a single-subject experiment, a media persona with millions of followers, and a company selling products derived from the experiment. Critics argue that the third compromises the first; Johnson says he shares, and sells, his protocol so that others can learn from it and try parts if they choose. Career Payments and venture capital Johnson grew up in a Mormon community in Utah, served a church mission in Ecuador, and studied at Brigham Young University and then at the University of Chicago's business school. In 2007 he founded Braintree, a payment processor. Braintree bought the peer-to-peer ","c":["people","longevity","cybernetics"],"k":"person","x":"contested","h":"present","w":1818,"n":7},{"s":"buck-institute","t":"Buck Institute for Research on Aging","d":"An independent research institute in Novato, California, opened in 1999 as the first in the world dedicated solely to the biology of aging.","g":["aging","biogerontology","research institutes","senescence","training","nonprofit"],"b":"Buck Institute for Research on Aging is an independent, nonprofit biomedical research institute in Novato, California, opened in 1999 and the first research organization in the world dedicated exclusively to the biology of aging. It is central to the modern geroscience programme both intellectually and institutionally. Much of the foundational work on Cellular senescence and the senescence-associated secretory phenotype was done there, and a substantial share of the field's principal investigators and company founders trained in its laboratories. Overview The institute is organized around the geroscience premise, which holds that the major chronic diseases of later life share upstream biological drivers and that intervening on those drivers would do more good than treating each disease separately. Its research is organized around aging mechanisms rather than around organ systems or diseases, which is unusual for a biomedical institute and was more unusual still when it opened. The institute lists 26 faculty and research professors, alongside a graduate programme and a translational arm intended to move findings toward companies. Its scale is modest relative to Calico or Altos labs: its federal filings report expenses of roughly $63 million in the fiscal year ending June 2025, against revenue of $57 million. Its output per dollar has been correspondingly high. History The instit","c":["organizations","longevity"],"k":"organization","x":"established","h":"present","w":1229,"n":12},{"s":"calico","t":"Calico Life Sciences","d":"Alphabet's independent biotechnology company, founded in 2013 to study the biology of aging and develop interventions against age-related disease.","g":["aging","biotech","drug discovery","comparative biology","google","research institutes"],"b":"Calico Life Sciences, originally the California Life Company, is a biotechnology company founded by Google in September 2013 to study the biology of aging and translate it into treatments for age-related disease. It was the first attempt by a large technology company to fund aging research at pharmaceutical scale, it operates with unusual secrecy, and after more than a decade its public output remains modest relative to the capital committed. Supporters and critics alike cite it as the reference case for what happens when the Geroscience hypothesis is given a large budget and a long horizon. Overview Calico's founding proposition was that aging is a tractable biological problem that pharmaceutical companies neglect because it is not a disease with a regulatory pathway, and that a company insulated from quarterly pressure could do the basic biology first and find the drug later. Arthur Levinson, formerly chief executive of Genentech and chairman of Apple, was named chief executive at launch and has held the role since. The company divides its work between discovery research (comparative biology, cellular aging mechanisms, computational genomics) and a drug development organization run in partnership with AbbVie. The two halves are connected loosely enough that Calico's most advanced clinical assets do not obviously derive from its aging research. History Google announced Calico ","c":["organizations","longevity"],"k":"organization","x":"established","h":"2030s","w":1240,"n":13},{"s":"caloric-restriction","t":"Caloric restriction","d":"Sustained reduction of energy intake without malnutrition, the oldest and most reproducible lifespan-extending intervention in animals and the least proven in humans.","g":["dietary restriction","aging","fasting","calerie","nutrient sensing","clinical trials"],"b":"Caloric restriction is a sustained reduction in energy intake, usually 20 to 40 per cent below what an animal would eat freely, while maintaining adequate vitamins, minerals and protein. In laboratory rodents it remains the most reproducible intervention in biogerontology: it extends median and maximum lifespan and delays most age-related pathologies. In primates the evidence genuinely conflicts, and in humans it stops at intermediate biomarkers measured over two years. Origins Underfeeding was linked to longevity before anyone had a mechanism. Clive McCay's 1935 experiments at Cornell showed that rats fed a restricted but nutritionally complete diet from weaning grew more slowly, matured later and lived substantially longer than freely fed controls. For decades the effect was attributed first to slowed growth, then to reduced metabolic rate, then to reduced oxidative damage. None of those explanations survived scrutiny. Restricted animals do not, in general, have lower mass-specific metabolic rates, and the free-radical account has weakened along with the wider retreat of that theory in mitochondrial biology. The current framing is nutrient sensing, which most catalogues of the Hallmarks of aging list as a distinct axis. That framing owes much to invertebrate genetics. Cynthia Kenyon's laboratory showed that partial loss of a single insulin/IGF-1-family receptor doubles nemato","c":["longevity"],"k":"intervention","x":"experimental","h":"present","w":1112,"e":"CALERIE, the only randomized trial in healthy non-obese adults, ran two years at roughly half the intended restriction and moved cardiometabolic and immune markers; no human lifespan data exist, and the two rhesus studies disagree.","a":"Requires no prescription and nothing to buy, since it is a change in eating; commercial fasting-mimicking formulations are sold direct to consumers.","r":"reversible","n":38},{"s":"cancer","t":"Cancer","d":"The class of diseases in which a somatic cell lineage escapes the controls on its own division, and the age-related cause of death that constrains most life-extension arguments.","g":["cancer","aging","oncology","somatic mutation","mortality","mechanisms","risk"],"b":"Cancer is the class of diseases in which a somatic cell lineage escapes the controls on its own division and invades tissue that is not its own. It is among the leading causes of death worldwide, and it is the disease whose incidence climbs most sharply with age. That combination puts it at the centre of nearly every argument this wiki covers about extending human life. It is the ceiling that life-extension arithmetic runs into and the risk that cell and gene therapies have to price in, and tumour suppression is the usual explanation for why two of the Hallmarks of aging exist at all. An age-related disease Cancer incidence rises as a steep power of age. Armitage and Doll fitted that relationship in 1954 and read the log-log slope as evidence that carcinogenesis requires six or seven rate-limiting steps in a single cell lineage, so that risk accumulates instead of arriving at a threshold. The multi-stage picture has been refined repeatedly since, but the demographic fact it was built on still holds: most cancers are diagnosed in people over 65, and age is the single strongest predictor in oncology. The pattern has exceptions. The American Cancer Society's 2026 statistical report projects roughly 2.1 million new US cases and 626,000 deaths, with 12% of diagnoses in people under 50 and colorectal cancer incidence in that group rising year on year. Part of the most recent accelera","c":["longevity","foundations"],"k":"concept","x":"established","h":"present","w":1619,"e":"Incidence rises steeply with age in every human population measured and US mortality rates have fallen by about a third since 1991; the claim that slowing aging would lower cancer risk has not been tested in people.","n":14},{"s":"casgevy","t":"Casgevy","d":"The first approved CRISPR-based medicine, which disrupts a fetal-haemoglobin repressor in a patient's own blood stem cells to treat sickle cell disease and beta thalassaemia.","g":["crispr","sickle cell disease","gene therapy","haemoglobin","drug pricing","clinical trials"],"b":"Casgevy (exagamglogene autotemcel) is a one-time cell therapy in which a patient's own blood-forming stem cells are edited outside the body with Crispr cas9 and returned, raising their production of fetal haemoglobin enough to compensate for a defective adult haemoglobin gene. Authorised in the United Kingdom in November 2023 and in the United States across December 2023 and January 2024, it is the first medicine based on CRISPR editing to reach regulatory approval anywhere. It treats two inherited disorders of the beta-globin gene: sickle cell disease and transfusion-dependent beta thalassaemia. How it works Casgevy does not repair the mutation that causes either disease; it works around it. Human beings make two different beta-like globin chains over a lifetime. Fetal haemoglobin, containing gamma-globin, dominates before birth and is switched off in the months afterwards, when adult beta-globin takes over. People who carry a beta-globin mutation are therefore healthy in utero and become ill only once the switch completes. A minority of people carry variants that keep fetal haemoglobin switched on into adulthood (hereditary persistence of fetal haemoglobin), and if they also inherit sickle mutations, their disease is markedly milder. That natural experiment defined the therapeutic target. The switch is enforced by the transcription factor BCL11A, identified as the repressor o","c":["genetics"],"k":"intervention","x":"emerging","h":"present","w":1201,"e":"In single-arm trials with no control group, most sickle cell recipients went at least twelve months without a vaso-occlusive crisis and most thalassaemia recipients stopped transfusions; follow-up is short.","a":"Approved in the United Kingdom in November 2023 and the United States shortly after; the US list price is about 2.2 million dollars, delivery is confined to authorised transplant centres, and early uptake was slow.","r":"irreversible","n":18},{"s":"cellular-senescence","t":"Cellular senescence","d":"A stable arrest of cell division, triggered by telomere attrition or stress, in which the arrested cell stays metabolically active and secretes inflammatory factors.","g":["aging","senescence","sasp","cell biology","cancer","mechanisms"],"b":"Cellular senescence is a stable exit from the cell cycle in which a cell stops dividing but does not die: it remains metabolically active, resists apoptosis and changes what it secretes. It is one of the Hallmarks of aging and one of the clearest cases of antagonistic pleiotropy in mammalian biology. The same arrest that prevents damaged cells from becoming tumours degrades the surrounding tissue when senescent cells accumulate with age. Discovery and definition Leonard Hayflick and Paul Moorhead reported in 1961 that normal human diploid fibroblasts divide a limited number of times in culture and then stop, contradicting the then-standard belief that vertebrate cells were immortal under good conditions. The limit is now attributed largely to progressive telomere shortening, but replicative exhaustion turned out to be only one route into the state. Senescence has no single definitive marker, a persistent methodological problem. Investigators typically require several features together: absence of proliferation markers, expression of the cyclin-dependent kinase inhibitors p16INK4a or p21CIP1, senescence-associated β-galactosidase activity detected at pH 6, loss of nuclear Lamin B1, and evidence of a persistent DNA damage response. Each of these also appears in cells that are not senescent. p16 expression in particular can be induced in macrophages as a reversible physiological r","c":["longevity"],"k":"concept","x":"established","h":"present","w":1169,"e":"The arrest was first described in cultured human fibroblasts and the markers appear in aged human tissue; every result showing that clearing senescent cells extends life is from mice, and randomized senolytic trials have not yet shown clinical benefit.","n":40},{"s":"closed-loop-life-support","t":"Closed-loop life support","d":"Engineering that regenerates a crew's air, water, and food from their own waste, reducing the resupply mass that otherwise makes long-duration spaceflight impossible.","g":["life support","spaceflight","recycling","bioregenerative","mars","closed ecology"],"b":"Closed-loop life support is the engineering of a habitat that regenerates the consumables its crew uses, meaning oxygen, water, and in the fully closed case food, from metabolic and system waste rather than carrying or resupplying them. It is a mass problem before it is a biology problem. An unrecycled crew consumes roughly five kilograms of oxygen, water and food per person per day, so a three-year Mars mission for four people implies a resupply mass no launch architecture can deliver. Every fraction of a loop that closes converts consumable mass into hardware mass and power, and the design question is where that trade turns favourable. How it works Four loops are usually treated separately. The atmosphere loop removes carbon dioxide, supplies oxygen, controls trace contaminants and manages pressure and humidity. On the International Space Station, carbon dioxide is captured on regenerable zeolite sorbent beds and oxygen is produced by electrolysing water. A Sabatier reactor closes part of the carbon loop by combining captured carbon dioxide with hydrogen from electrolysis to make methane and water. The methane is vented, so hydrogen, and with it water, leaves the system permanently. Closing that last step requires methane pyrolysis to recover the hydrogen, which has been developed but not operationally flown at scale. The water loop is the most closed in practice. Urine is pr","c":["space"],"k":"technology","x":"emerging","h":"2030s","w":1382,"e":"Crews have lived for months on regenerated air and water aboard the ISS and in sealed ground facilities such as BIOS-3; no flown system has closed the food loop, and essentially every calorie eaten in orbit was launched.","a":"Nothing to obtain: these are one-off agency and research systems, and flight-qualified hardware exists only aboard the ISS and in a handful of sealed ground facilities.","r":"reversible","n":5},{"s":"cochlear-implant","t":"Cochlear implant","d":"An implanted device that restores a functional sense of hearing by stimulating the auditory nerve with electrical pulses, bypassing the ear's damaged hair cells.","g":["hearing","sensory restoration","implants","deafness","neuroprosthetics","disability"],"b":"Cochlear implants are surgically implanted devices that restore a usable sense of hearing by delivering electrical pulses directly to the auditory nerve, replacing the function of the inner ear's hair cells rather than amplifying sound as a hearing aid does. They are the most widely deployed neuroprosthesis in existence and the only one that routinely restores a lost sense well enough for most adult recipients to hold a conversation. They are also the subject of the oldest live ethical dispute in Neuroprosthetics, because a substantial part of the Deaf community regards deafness as a linguistic identity rather than a deficit to be corrected. How it works Sound reaches a microphone on a behind-the-ear or off-the-ear processor. The processor splits the signal into a bank of frequency channels, extracts the slowly varying amplitude envelope of each, and converts those envelopes into a schedule of biphasic current pulses. The schedule is transmitted through the intact skin by radio-frequency coupling across a magnetically aligned coil pair to a receiver-stimulator seated in a recess milled into the temporal bone. From there a wire bundle runs to an electrode array threaded through the round window into the scala tympani, roughly one to one-and-a-half turns along the cochlear spiral. The array exploits tonotopy. The cochlear base responds to high frequencies and the apex to low ones","c":["cybernetics","bodies"],"k":"technology","x":"established","h":"present","w":1491,"e":"More than 700,000 people have been implanted; most postlingually deafened adults reach open-set sentence recognition in quiet, and a prospective multicentre cohort found earlier-implanted children gained spoken language faster.","a":"Approved and routinely reimbursed in high-income countries; device, surgery and years of audiological programming run to tens of thousands of dollars, and most of the world's profoundly deaf people never receive one.","r":"difficult","n":20},{"s":"coffee-and-aging","t":"Coffee and aging","d":"The claim that habitual coffee drinking slows human aging, built on consistent cohort links to lower mortality that genetic studies have not confirmed as causal.","g":["coffee","caffeine","diet","epidemiology","causal inference","aging","healthspan"],"b":"Coffee and aging names a long-running epidemiological finding and the claim built on it: that people who habitually drink moderate amounts of coffee die at lower rates than people who do not, and that coffee therefore slows some part of human aging. The association is among the most often replicated in nutritional epidemiology. Whether coffee causes it is unresolved: the evidence is almost entirely observational, the genetic studies designed to test causality have mostly been null, and no randomized trial has measured survival. The epidemiological signal The modern literature took shape with the NIH-AARP Diet and Health Study, which followed about 400,000 American men and women aged 50 to 71 between 1995 and 2008. In age-adjusted models coffee drinkers were more likely to die. They were also more likely to smoke, and once smoking and other confounders were adjusted for, the direction reversed: men drinking two or three cups a day had a hazard ratio for death of 0.90 relative to non-drinkers, and women drinking four or five cups 0.84. Inverse associations appeared for deaths from heart disease, stroke, respiratory disease, and several other causes, but not from Cancer. Coffee intake was measured once, at baseline, and the authors wrote that their data could not determine whether the finding was causal. The pattern has since been reproduced in many populations. A 2017 umbrella re","c":["longevity"],"k":"intervention","x":"contested","h":"present","w":1609,"e":"Large prospective cohorts link moderate coffee drinking to roughly 10 to 17 percent lower all-cause mortality; Mendelian randomization studies have not supported causality, and no randomized trial has tested survival.","a":"Sold as an ordinary food and drink almost everywhere, cheaply and without prescription; no regulator recognizes coffee or any of its constituents as a treatment for aging.","r":"reversible","n":2},{"s":"colossal-biosciences","t":"Colossal Biosciences","d":"A Texas biotechnology company founded in 2021 to recreate extinct species by editing the genomes of living relatives, and to spin out conservation technology from that work.","g":["de-extinction","genome editing","conservation","ancient dna","biotech","mammoth"],"b":"Colossal Biosciences is a privately held biotechnology company founded in 2021 by the entrepreneur Ben Lamm and the geneticist George church to pursue De extinction: producing animals resembling extinct species by editing the genomes of their closest living relatives. Its stated flagship targets are the woolly mammoth, the thylacine and the dodo. It is the best-funded organization ever to work on the problem and also the most criticized, chiefly over whether an edited proxy animal can properly be described as a de-extincted species. Overview Colossal does not clone extinct animals. No viable cell has ever been recovered from a species that was already extinct, and the only extinct animal ever cloned, the bucardo, came from tissue banked while its last individual was still alive, as De extinction describes. The company's method is comparative. It sequences ancient DNA to identify the genetic differences between the extinct species and a living relative, selects a subset of those differences judged to underlie the phenotype of interest, and introduces them into the relative's cells using Crispr cas9 and related tools including Base editing. An animal is then produced by somatic cell nuclear transfer (the technique behind Dolly and her successors) or by germline transmission. For the mammoth the living relative is the Asian elephant; for the thylacine, the fat-tailed dunnart; for ","c":["organizations","genetics"],"k":"organization","x":"contested","h":"late 2020s","w":1396,"n":3},{"s":"compression-of-morbidity","t":"Compression of morbidity","d":"The hypothesis that chronic illness can be postponed into a shorter interval before death, so that added years of life are healthy ones.","g":["aging","healthspan","public health","disability","demography","health policy"],"b":"Compression of morbidity is the hypothesis that the age at which chronic illness and disability begin can be pushed back faster than the age of death, shortening the period of poor health at the end of life. The Stanford physician James F. Fries set it out in 1980, and it has shaped how health systems and gerontologists think about the value of longer life ever since. Whether it has actually occurred in any national population remains disputed. The 1980 hypothesis Fries argued from two premises. The first was that human lifespan has a natural ceiling, which he put at an average biological limit of roughly 85 years. As premature death was eliminated, the survival curve would become increasingly rectangular, with most people dying in a narrow band near that age. The second premise was that the onset of chronic disease is more modifiable than the age of death, because it is driven substantially by behavior: smoking, inactivity, diet and injury. If both held, improving those behaviors would push illness onset later while the age of death stayed roughly fixed, squeezing morbidity into a shorter terminal interval. Fries pictured a person who remains functional into their eighties and then declines rapidly over months. The first premise has not held. Maximum lifespan shows no sign of the fixed ceiling Fries assumed, and mean life expectancy for women in the longest-lived countries has","c":["longevity","society"],"k":"concept","x":"contested","h":"present","w":1314,"e":"Disability rates in the United States and several European countries fell through the 1980s and 1990s and then stalled, while years lived with diagnosed chronic disease rose; no national population has been shown to compress morbidity.","n":30},{"s":"connectomics","t":"Connectomics","d":"The mapping of complete wiring diagrams of nervous systems, from macroscale fibre tracts down to every synapse in a volume of tissue.","g":["connectome","electron microscopy","neuroscience","brain mapping","segmentation","neural circuits"],"b":"Connectomics is the mapping of the complete set of connections in a nervous system. The term covers two very different enterprises that share a name: macroscale connectomics, which uses diffusion MRI to trace fibre bundles between brain regions in living people, and synapse-resolution connectomics, which uses electron microscopy on fixed tissue to identify every neuron and every synapse in a volume. The second is the one relevant to Whole brain emulation and to circuit neuroscience. It is destructive and slow, and since the mid-2020s it has been producing complete brains for the first time. The word was proposed in 2005, by analogy with the genome, for a comprehensive structural description of a nervous system. The practice is much older: the complete wiring diagram of Caenorhabditis elegans, reconstructed by hand from electron micrographs over more than a decade, was published in 1986 and remains the only nervous system whose full anatomy has been known for long enough to test what such knowledge is worth. Scales and methods Macroscale connectomes derive from diffusion-weighted MRI, which infers the orientation of white matter tracts from the directional diffusion of water. Resolution is on the order of a millimetre, tractography algorithms are prone to false positives at fibre crossings, and the output is a region-by-region matrix rather than a circuit. The NIH Human Connecto","c":["minds"],"k":"technology","x":"emerging","h":"2030s","w":1390,"e":"Synapse-resolution mapping in humans has reached one cubic millimetre of fixed cortex from a single person; complete connectomes exist only for a nematode and a fly, and no mammalian brain has been mapped in full.","a":"Nothing to purchase as a service: the published datasets are freely downloadable, and the imaging and segmentation are done by a handful of consortium-scale groups.","r":"irreversible","n":18},{"s":"consumer-blood-testing","t":"Consumer blood testing","d":"The sale of clinical laboratory panels directly to asymptomatic consumers as preventive medicine, where accurate assays meet a screening logic that guidelines reject.","g":["diagnostics","screening","overdiagnosis","preventive medicine","biomarkers","direct-to-consumer"],"b":"Consumer blood testing is the sale of clinical laboratory panels directly to people who have no symptoms and no physician's referral, marketed as preventive or proactive medicine. The assays themselves are ordinary hospital chemistry, run in certified laboratories, and mostly accurate. The dispute is over the inference drawn from them: whether measuring dozens or hundreds of analytes in a person who feels well yields information that makes them healthier, or mainly produces abnormal-looking numbers. What is sold The transaction works the same way across sellers. A consumer orders a panel online; a contracted physician network signs the requisition where state law still requires a clinician's order; blood is drawn at a commercial service centre, by a mobile phlebotomist, or through a mail-in capillary kit. Results arrive in an application rather than a consultation, colour-coded against a range and accompanied by generated advice on diet, Dietary supplements, sleep and training. Quest and Labcorp, the dominant American reference laboratories, sell consumer-initiated versions of the tests they run for hospitals. Everlywell built its business on mail-in kits aimed at single questions; InsideTracker pairs a modest panel with algorithmic nutrition advice; Function Health, co-founded by the physician and author Mark Hyman, sells an annual membership covering on the order of a hundred","c":["longevity","society"],"k":"technology","x":"contested","h":"present","w":1559,"e":"The individual assays are standard clinical chemistry validated in people; no randomized trial has shown that broad panels in asymptomatic adults reduce illness or death, and trials of periodic general health checks found no mortality benefit.","a":"Sold online in most US states and in several other countries without a physician referral; single panels cost tens to hundreds of dollars and annual memberships several hundred, almost never reimbursed.","r":"context","n":16},{"s":"continuous-glucose-monitoring","t":"Continuous glucose monitoring","d":"A wearable sensor that reports glucose in the fluid between cells every few minutes, well established in diabetes and of unproven value to people without it.","g":["diabetes","biosensors","metabolic health","wearables","self-tracking","measurement"],"b":"Continuous glucose monitoring uses a coin-sized sensor worn on the skin, with a filament sitting in the tissue beneath it, to report glucose concentration in interstitial fluid every one to five minutes. In type 1 diabetes and in insulin-treated type 2 diabetes the technology is established, reimbursed, and supported by randomized trials. Since 2024 the same class of sensor has been sold over the counter in the United States to adults who do not use insulin, including people without diabetes, a market in which no trial has shown that wearing one improves health. How it works An applicator drives a flexible filament a few millimetres into subcutaneous tissue and leaves an adhesive patch on the skin. The filament is an enzyme electrode: an immobilized enzyme, usually glucose oxidase, reacts with glucose diffusing in from the surrounding fluid, and the electronics read the resulting current, which rises and falls with concentration. A transmitter sends a value to a phone every one to five minutes. Current consumer sensors are factory-calibrated, need a warm-up period after insertion before they display anything, and are discarded after roughly ten to fifteen days. The sensor reads interstitial fluid, not blood. Glucose reaches interstitial fluid by diffusion out of capillaries, so the interstitial value trails the blood value by something on the order of five to fifteen minutes, a","c":["longevity","cybernetics"],"k":"technology","x":"established","h":"present","w":1648,"e":"Randomized trials in type 1 and insulin-treated type 2 diabetes show lower HbA1c and less hypoglycemia; no trial in people without diabetes has shown a benefit on any health outcome.","a":"Prescribed and widely reimbursed for insulin-treated diabetes in wealthy countries; over-the-counter sensors have been sold in the United States since 2024, paid out of pocket.","r":"reversible","n":7},{"s":"cortical-visual-prosthesis","t":"Cortical visual prosthesis","d":"An implanted device that bypasses the eyes and optic nerves and electrically stimulates the visual cortex, producing spots of light that blind users learn to read as crude images.","g":["vision","blindness","phosphenes","visual cortex","sensory restoration","neuroprosthetics","implants"],"b":"A cortical visual prosthesis is an implanted device that produces visual sensations in a blind person by electrically stimulating the visual cortex directly, skipping the eyes and optic nerves altogether. Each stimulated site evokes a phosphene, a small spot of light at a fixed place in the visual field, and a camera-driven processor chooses which sites to stimulate so that the pattern of phosphenes outlines what the camera sees. Because it needs neither a working retina nor an optic nerve, it is aimed at people blinded by glaucoma, optic nerve injury or loss of both eyes, for whom a Retinal implant cannot work. As of October 2026 every such device remains investigational. How it works The primary visual cortex holds a retinotopic map: neighbouring points in the visual field are represented by neighbouring patches of cortex, with central vision given far more tissue than the periphery. Stimulating one patch therefore produces a phosphene at a predictable location. Brindley and Lewin found in 1968 that the phosphene map they evoked \"agrees roughly\" with the classical maps derived from war wounds, and that phosphenes from electrodes 2.4 mm apart could be told apart. Two electrode designs compete. Surface arrays sit on the cortex, as in Ecog interfaces, and need relatively large currents. Penetrating arrays such as the Utah array put electrode tips inside the cortex, near the neur","c":["cybernetics"],"k":"technology","x":"experimental","h":"2030s","w":1992,"e":"Small feasibility studies in blind adults show phosphene mapping, letter and motion discrimination, and implants in a registered trial working for up to six years; the trials have enrolled only people who once had sight.","a":"Available only to adults enrolled in a few feasibility studies in the US and Spain that require years of prior sight; no cortical visual prosthesis has marketing approval as of October 2026.","r":"difficult","n":5},{"s":"crispr-cas9","t":"CRISPR–Cas9","d":"A bacterial defence system repurposed as a programmable DNA-cutting tool, in which a short guide RNA directs the Cas9 enzyme to a chosen sequence in almost any genome.","g":["crispr","genome editing","molecular biology","gene therapy","nobel prize","biotechnology"],"b":"CRISPR-Cas9 is a two-part molecular machine (a short guide RNA and a DNA-cutting protein) that bacteria use to destroy invading viral genomes and that biologists have repurposed to cut a chosen sequence in almost any organism. Its advantage over earlier editing platforms is that the target is specified by an interchangeable twenty-nucleotide RNA rather than by a redesigned protein, so retargeting takes days instead of months. Cutting, however, is only the first step. What an edit becomes depends on how the cell repairs the break, and that repair is the part biologists control least. Origins in bacterial immunity The sequences now called CRISPR (clustered regularly interspaced short palindromic repeats) were first noticed in 1987 by Yoshizumi Ishino's group at Osaka University, who found an odd series of repeats downstream of a gene they were sequencing for unrelated reasons and could not explain them. Through the 1990s and early 2000s the same architecture turned up in many bacteria and archaea. Francisco Mojica at the University of Alicante catalogued the arrays, coined the acronym with Ruud Jansen, and proposed that the sequences between the repeats, called spacers, matched viral and plasmid DNA, implying an adaptive immune function. The experimental proof came in 2007, when Rodolphe Barrangou, Philippe Horvath and colleagues at the food-ingredients company Danisco challenged","c":["genetics","foundations"],"k":"technology","x":"established","h":"present","w":1760,"e":"One approved medicine, Casgevy, edits a patient's own blood stem cells outside the body; in vivo editing has durably lowered the disease-causing protein in transthyretin amyloidosis, and heritable editing is unapproved in every country with a relevant law.","a":"Reagents are ordinary catalogue items sold to any laboratory; the one approved medicine built on the platform treats two inherited blood disorders and is priced in the millions of dollars per patient.","r":"irreversible","n":45},{"s":"cryonics","t":"Cryonics","d":"The practice of preserving legally dead people at cryogenic temperatures in the hope that future medicine can repair and revive them.","g":["cryopreservation","vitrification","life extension","death","cryobiology","revival"],"b":"Cryonics is the preservation of a legally dead human body or brain at cryogenic temperatures, on the premise that the damage of dying and of preservation itself may one day be reversible by medicine that does not yet exist. Cryonics is not offered as a treatment and makes no claim to work now; it is a wager that the information constituting a person survives the process and that some future technology will be able to read or restore it. The practice has been closely associated with Transhumanism since both emerged in the 1960s and 1970s, and remains marginal to mainstream medicine. How it works The procedure begins at legal death, which in most jurisdictions means cardiopulmonary arrest and a physician's pronouncement. Nothing may be done before that point, and the constraint shapes the whole practice: the ideal case is a patient who dies expectedly, with a standby team present, and the worst case is an unwitnessed death discovered days later. Stabilization Immediately after pronouncement, the team restores circulation mechanically and begins external cooling with ice, sometimes with drugs intended to limit reperfusion injury and blood clotting. The aim is to reduce the interval of warm ischemia during which cells continue metabolizing without oxygen. Ischemic injury before perfusion is generally regarded, including by cryonics organizations themselves, as the largest source of","c":["longevity","bodies"],"k":"technology","x":"contested","h":"indefinite","w":1878,"e":"Fewer than a thousand people have been cryopreserved and none has been revived; no mammal has been recovered from cryogenic temperature, and the strongest whole-organ result is a vitrified rat kidney rewarmed and transplanted.","a":"Sold by a handful of member organizations; Alcor's minimum funding is $200,000 whole-body and $80,000 neuro, the Cryonics Institute charges several times less, and most members pay by life insurance.","r":"irreversible","n":27},{"s":"cynthia-kenyon","t":"Cynthia Kenyon","d":"American molecular geneticist whose 1993 finding that a single daf-2 mutation doubles the lifespan of C. elegans made aging a tractable genetic problem.","g":["aging","genetics","c. elegans","insulin signaling","foxo","biogerontology"],"b":"Cynthia Kenyon is an American molecular geneticist whose laboratory showed in 1993 that a mutation in a single gene, daf-2, roughly doubles the lifespan of the nematode Caenorhabditis elegans, and that the extension depends entirely on a second gene, daf-16. The long-lived animals stayed active instead of merely surviving longer, a detail that shaped how the result was received. Before that experiment, aging was widely treated as dispersed damage with no control point and no serious genetics; afterwards it was a pathway. Since 2014 she has been vice president of aging research at Calico. Career Kenyon studied biochemistry at the University of Georgia and took a doctorate at the Massachusetts Institute of Technology with Graham Walker. There she showed that DNA-damaging agents switch on a specific set of genes in Escherichia coli, several of them involved in DNA repair, which was early evidence that a cell answers damage with a coordinated transcriptional response. She then joined Sydney Brenner's group at the MRC Laboratory of Molecular Biology in Cambridge, where C. elegans had been built into a model organism and its cell lineage was being traced cell by cell. She joined the University of California, San Francisco in the mid-1980s and worked first on how Hox genes pattern the worm's body. By her own account, the turn to aging was a deliberate move into a question the field co","c":["people","longevity"],"k":"person","x":"established","h":"present","w":1643,"n":15},{"s":"david-sinclair","t":"David Sinclair","d":"Australian-American biologist at Harvard known for sirtuin and NAD+ research, the information theory of aging, and disputes over the strength of his public claims.","g":["aging","sirtuins","nad","epigenetics","reprogramming","biogerontology"],"b":"David Sinclair is an Australian-American molecular biologist at Harvard Medical School whose laboratory has worked on yeast aging, sirtuins, NAD+ metabolism and epigenetic rejuvenation. He is among the most publicly visible biogerontologists and the most criticized within the field. The criticism is aimed less at the underlying experiments than at how far his public statements travel beyond them. Career Sinclair completed a doctorate in molecular genetics at the University of New South Wales and moved to MIT as a postdoctoral researcher with Leonard Guarente, where he identified extrachromosomal ribosomal DNA circles as a driver of replicative aging in budding yeast. He joined Harvard Medical School in 1999 and co-directs the Paul F. Glenn Center for Biology of Aging Research there. He has founded or co-founded a series of companies across the aging sector, including Sirtris Pharmaceuticals, Life Biosciences and the consumer Biological age testing firm Tally Health, and he holds advisory positions across many more. Sirtuins and resveratrol The sirtuins are NAD+-dependent deacetylases. Guarente's laboratory had linked the yeast homolog SIR2 to lifespan and to the response to Caloric restriction, which raised the question of whether small molecules could reproduce that response by activating the mammalian equivalents. In 2003 Sinclair's group reported that resveratrol, a polyphen","c":["people","longevity"],"k":"person","x":"contested","h":"present","w":1061,"n":12},{"s":"de-extinction","t":"De-extinction","d":"The attempt to recreate extinct organisms, in practice by editing a close living relative to carry some of the extinct animal's traits rather than restoring the species itself.","g":["conservation","genome editing","cloning","ancient dna","biodiversity","proxy species"],"b":"De-extinction is the attempt to bring back an extinct organism. In practice, no project restores an extinct species. What the working programmes produce is a proxy: a living species edited to carry some of the extinct animal's genetic variants and, if the edits work, some of its traits. Whether that constitutes de-extinction is a question of definition, and the definition has become the main point of public dispute. Three routes, only one of which is genomic Back-breeding selectively breeds living descendants for traits resembling the ancestral form. The Heck cattle of the 1920s and the later Tauros programme aimed at something aurochs-like; the Quagga Project in South Africa breeds plains zebras for reduced striping. These produce animals that look the part and are genomically ordinary. Cloning by somatic cell nuclear transfer requires intact cells, which extinction usually precludes. The one success remains the bucardo, a Pyrenean ibex whose last individual was tissue-sampled before her death in 2000; a cloned kid was born in 2003 and died within minutes from a lung malformation. The same technique is used productively for species that are endangered rather than extinct, as in the cloning of a black-footed ferret and a Przewalski's horse from cell lines cryopreserved decades earlier. That use, genetic rescue, works. The mechanics are covered in Human cloning. Genome editing o","c":["genetics"],"k":"technology","x":"contested","h":"2030s","w":1188,"e":"Nothing here has been applied to people; the only extinct animal ever brought to term was a cloned Pyrenean ibex that died within minutes of birth in 2003.","a":"Nothing to obtain: no restored species exists, and the work runs inside a small number of venture-funded and academic programmes.","r":"irreversible","n":7},{"s":"decellularized-scaffolds","t":"Decellularized scaffolds","d":"Donor tissues stripped of their cells to leave an extracellular matrix scaffold, used as surgical implants and as a route to rebuilding whole organs from a preserved vascular tree.","g":["extracellular matrix","regenerative medicine","transplantation","biomaterials","research misconduct","tissue engineering"],"b":"Decellularized scaffolds are tissues or whole organs from which the cells have been removed, leaving the extracellular matrix intact. The matrix retains the tissue's three-dimensional architecture, its mechanical properties, its basement membranes and, critically for organ work, its vascular tree. Acellular matrix products of this kind are routine in surgery. Whole decellularized organs, reseeded with a recipient's cells, are the most structurally complete approach anyone has to growing a replacement organ, and remain a rodent-scale result. How it works Decellularization removes cellular material without destroying the matrix that surrounds it. Doing so is a balance, since every agent aggressive enough to lyse cells also degrades matrix components. Ionic detergents such as sodium dodecyl sulfate strip cells efficiently but denature proteins and remove glycosaminoglycans and matrix-bound growth factors. Non-ionic detergents such as Triton X-100 are gentler and less complete. Most protocols combine them with enzymatic steps, usually a nuclease to digest residual DNA, and with physical treatments such as freeze-thaw cycling. For thin tissues the agents are applied by immersion and agitation. For whole organs the decisive technique is perfusion decellularization: cannulating the organ's artery and pushing detergent through the native vasculature, so that every cell is reached throu","c":["bodies"],"k":"technology","x":"emerging","h":"2030s","w":1344,"e":"Acellular matrix implants are in routine surgical use in people, and a small uncontrolled study reported new muscle formation at sites of traumatic muscle loss; recellularized whole organs remain a rodent result.","a":"Acellular dermis, submucosa, heart valves and nerve grafts are approved surgical products in wide use; no recellularized whole organ is available at any price.","r":"difficult","n":11},{"s":"deep-brain-stimulation","t":"Deep brain stimulation","d":"A surgical therapy in which implanted electrodes deliver continuous electrical pulses to specific deep brain structures to suppress the symptoms of movement and psychiatric disorders.","g":["neuromodulation","parkinsons","implants","psychiatry","closed-loop","neuroethics"],"b":"Deep brain stimulation (DBS) is the delivery of continuous electrical pulses through electrodes implanted in specific subcortical structures, controlled by a pulse generator placed under the skin of the chest. It is the most widely used implanted neurotechnology after the Cochlear implant, and it is unusual among the technologies covered on this wiki in being both routine and poorly understood: DBS reliably suppresses the motor symptoms of Parkinson's disease without a settled account of why. How it works A quadripolar or segmented lead, roughly 1.3 mm in diameter, is placed stereotactically with millimetre accuracy, often with the patient awake so that clinical response and side effects can be tested intraoperatively. The lead is tunnelled under the scalp and connected to an implanted pulse generator. Stimulation is typically delivered at 130-185 Hz with pulse widths of tens of microseconds, and each contact can be turned on independently, allowing a clinician to steer the field away from structures that produce side effects. The mechanism is contested. High-frequency stimulation was first assumed to inhibit the target, because its effects resemble those of a lesion. The evidence now points elsewhere. Stimulation excites axons more readily than cell bodies, so a high-frequency train imposes a regular, information-free firing pattern on the output pathway. The result is an \"inf","c":["cybernetics"],"k":"intervention","x":"established","h":"present","w":1420,"e":"Randomized trials in adults with Parkinson's disease report large gains in mobility and quality of life against best medical therapy, and the device is in routine clinical use; two randomized trials in depression were halted for futility.","a":"Approved for Parkinson's disease, essential tremor, dystonia and drug-resistant epilepsy, reimbursed by many high-income systems, and delivered only at specialist centres; psychiatric use is investigational beyond a US exemption for OCD.","r":"difficult","n":28},{"s":"designer-babies","t":"Designer babies","d":"A popular term for children whose traits are chosen before birth, covering a real but narrow practice of embryo selection and a largely hypothetical practice of embryo editing.","g":["reproduction","embryo selection","germline","bioethics","genomics","enhancement"],"b":"Designer babies is a popular term for children whose genetic characteristics have been deliberately chosen by their parents. It covers two very different things. One is Embryo selection, which is routine in fertility clinics and can reliably deliver only a short list of outcomes. The other is heritable Germline editing, which has been attempted once, illegally, and would face a different and harder set of technical obstacles. Most public argument treats the two as a single prospect, and much of the confusion around the term starts there. Origins of the term The phrase is journalistic, not technical. It follows the pattern of \"designer drugs\", was in wide circulation by the 1990s, and attached itself to a sequence of real clinical developments. In vitro fertilisation produced its first birth in 1978; preimplantation genetic diagnosis followed in 1990, when a British team biopsied embryos and selected female ones for couples at risk of X-linked disease. The film Gattaca fixed the popular image in 1997, some years before any of the genomic tools needed to realise it existed. A defining case arrived in 2000, when a couple used preimplantation diagnosis both to avoid Fanconi anaemia and to select an embryo whose tissue type matched their affected daughter's, so that cord blood from the resulting child could treat her. The \"saviour sibling\" framing dominated coverage for a decade. It","c":["reproduction","society"],"k":"concept","x":"contested","h":"present","w":1373,"n":15},{"s":"dietary-supplements","t":"Dietary supplements","d":"Vitamins, minerals, botanicals, and other compounds sold without pre-market approval, whose large randomized trials have repeatedly failed to show benefit in well-nourished adults.","g":["supplements","regulation","vitamins","clinical trials","consumer health","antioxidants"],"b":"Dietary supplements are vitamins, minerals, botanical extracts, amino acids, and other compounds sold for ingestion outside the drug-approval system. In the United States the category was created by statute in 1994 and treated as a kind of food: no agency reviews a product for safety or efficacy before it reaches a shelf. The category contains established medicine, chiefly the correction of documented deficiencies, wrapped in a much larger commercial layer of compounds sold for healthy aging, and the large randomized trials of that second layer have mostly returned null or harmful results. The regulatory bargain The Dietary Supplement Health and Education Act of 1994 (DSHEA) defines a dietary supplement as a food rather than a drug or a food additive. The classification has structural consequences. A manufacturer is responsible for concluding that its product is safe, but need not demonstrate that conclusion to anyone before selling it, and need not show any benefit at all. To remove a product, the Food and Drug Administration must establish that it presents a significant or unreasonable risk, and it must do so after the product is on the market, often after people have been hurt. Ingredients not sold in the United States before October 1994 require a pre-market notification rather than an approval, and compliance with even that is widely acknowledged to be partial. Labels may ","c":["longevity","society"],"k":"intervention","x":"contested","h":"present","w":1721,"e":"Correcting a documented deficiency is established medicine, but large randomized trials in well-nourished adults have been null for cancer and cardiovascular endpoints, and beta-carotene and vitamin E raised cancer incidence in some groups.","a":"Sold without prescription in supermarkets, pharmacies, and online almost everywhere; in the United States no product needs approval before sale, and monthly cost ranges from a few dollars to several hundred.","r":"reversible","n":30},{"s":"differential-technological-development","t":"Differential technological development","d":"Nick Bostrom's proposal to influence the order in which technologies arrive, hastening protective ones and delaying dangerous ones, rather than trying to halt progress.","g":["governance","risk","biosecurity","existential risk","policy","coordination"],"b":"Differential technological development is the proposal that, since stopping technological progress is neither feasible nor desirable, effort should go into changing the order in which capabilities arrive: accelerating technologies that reduce risk and delaying those that create it. It does not claim that dangerous technologies can be prevented indefinitely. Its claim is that arrival order determines whether a society meets a hazard with defences already in place or without them. The proposal Nick bostrom's formulation asks policymakers to retard the development of dangerous and harmful technologies, particularly those that raise Existential risk, and to accelerate beneficial ones, particularly those that reduce risks posed by nature or by other technologies. It differs from ordinary risk regulation in three ways. It is comparative. The target is the gap between paired capabilities (offence and defence, capability and interpretability, synthesis and detection) rather than any technology's absolute pace. It is strategic rather than prohibitive. It concedes that a determined actor will eventually obtain a capability and asks only what else will exist by then. It is neutral about totals. In principle it is compatible with faster overall progress, provided the sequencing improves, so both people who want less technology and people who want more invoke it. Origins The principle appea","c":["society","foundations"],"k":"concept","x":"contested","h":"present","w":1265,"n":20},{"s":"digital-immortality","t":"Digital immortality","d":"The persistence of a person in digital form after death, ranging from chatbot reconstructions built from their data to the hypothetical emulation of their brain.","g":["griefbots","digital afterlife","uploading","identity","data ethics","postmortem privacy"],"b":"Digital immortality is the persistence of a person in computational form after biological death. The term covers two things that share almost nothing except a marketing vocabulary. The weak form builds a conversational model from what a person left behind (messages, recordings, video, social media) and produces something that talks like them. The strong form is Mind uploading: running an emulation derived from the structure of the person's brain, which would on some accounts be the person. The weak form exists and is sold commercially. The strong form has no working demonstration at any scale. The weak form The idea entered wide circulation in 2016, when a chatbot built from a dead friend's text messages was reported at length and read by many as a glimpse of something larger. A reconstruction is a stylistic model. Given enough text and audio, a language model can be conditioned or fine-tuned to reproduce a person's turns of phrase, opinions, and voice; add synthesized speech and a generated face and the output is a video call with a dead relative. Nothing about the underlying brain is involved, and the model has access only to what was recorded. Where the source data is thin, the system fills gaps by generalizing from its training corpus, which means it will confidently produce statements the person never made and could not have made. The lineage runs back through lifelogging,","c":["minds","society"],"k":"concept","x":"emerging","h":"present","w":1209,"n":8},{"s":"disability-rights-and-enhancement","t":"Disability rights and enhancement","d":"The disability-rights critique of selection and enhancement, centred on the expressivist objection, the social model, and the difference between curing and accommodating.","g":["disability","bioethics","neurodiversity","selection","accessibility","deafness"],"b":"Disability rights and enhancement covers the arguments made by disability scholars and activists against biomedical selection and enhancement, and the responses to them. Neither side wants disabled people to suffer. The dispute concerns whether the appropriate target of intervention is the body or the environment, about what a decision to select against a trait says to people who have it, and about who is entitled to make that judgment. The social model British disability activists in the 1970s drew a distinction that reorganised the field, between impairment, a feature of a body, and disability, the disadvantage produced when an environment is built for bodies of a different kind. On this account stairs, rather than paralysis, are what disable a wheelchair user. The formulation appeared in a 1976 statement by a UK activist organisation and was named the social model by Michael Oliver in the early 1980s. The model's practical effect has been large. It moved policy from charity and rehabilitation toward access and civil rights, and it underwrites the UN Convention on the Rights of Persons with Disabilities, adopted in 2006, which frames disability as arising from interaction between impairment and barriers rather than as a property of individuals. Few scholars now defend its strong form, which holds that impairment contributes nothing to disadvantage, and that includes scholars ","c":["society","enhancement"],"k":"concept","x":"established","h":"present","w":1406,"n":30},{"s":"dna-nanotechnology","t":"DNA nanotechnology","d":"The use of DNA as a construction material rather than a carrier of genes, folding programmed sequences into nanoscale shapes, devices, and logic-gated containers.","g":["nanomedicine","dna origami","self-assembly","molecular machines","drug delivery","biosensing"],"b":"DNA nanotechnology treats DNA as a building material rather than as genetic information. Because base pairing is predictable, a set of synthetic strands can be designed so that the only low-energy configuration they can adopt is a particular shape, and that shape then assembles itself when the strands are mixed and cooled. The field has produced nanoscale objects of arbitrary geometry, molecular machines that walk and compute, and containers that open in response to a chosen biological signal. How it works The field starts from the fact that DNA can form structures other than the double helix. Branched junctions occur naturally during recombination, but they migrate. Nadrian Seeman proposed in 1982 that a junction built from sequences with no symmetry could be made immobile, and that immobile junctions could be linked into a rigid lattice. The idea turns DNA from a linear molecule into a construction kit with programmable connectivity. DNA origami, introduced by Paul Rothemund in 2006, made the approach practical. A single long scaffold strand, usually the genome of the M13 bacteriophage at around 7,200 bases, is folded into a target shape by roughly two hundred short synthetic \"staple\" strands, each designed to bind two or three distant regions of the scaffold and hold them together. Mixing scaffold and staples and annealing over a few hours yields the designed object in enorm","c":["nanomedicine","genetics"],"k":"technology","x":"experimental","h":"2030s","w":1435,"e":"No DNA nanostructure has entered a human trial; the strongest results are logic-gated payload release on cultured human cells and thrombin-loaded tubes that slowed tumour growth in mice.","a":"Research use only: scaffolds and staple strands are ordinary laboratory reagents, and no DNA nanostructure is available as a medical product anywhere.","r":"reversible","n":13},{"s":"dog-aging-project","t":"Dog Aging Project","d":"A longitudinal study of aging in tens of thousands of companion dogs, paired with TRIAD, a randomized placebo-controlled trial testing whether rapamycin extends canine lifespan.","g":["aging","dogs","rapamycin","geroscience","clinical trials","open science","veterinary medicine"],"b":"The Dog Aging Project is a long-term study of aging in companion dogs, anchored at the University of Washington and Texas A&M University, that has enrolled more than 50,000 pet dogs since opening in late 2019. It pairs an open-data longitudinal cohort with TRIAD, a double-blind, placebo-controlled trial testing whether Rapamycin extends lifespan and Healthspan in normally aging dogs. Its investigators describe TRIAD as the first rigorous lifespan trial of a drug against aging conducted outside the laboratory in any species. Overview The project occupies a deliberate middle position in the geroscience pipeline. Rapamycin's lifespan record was built in mice, most rigorously by the Interventions testing program, but inbred laboratory mice live in cages, eat one diet, and die of a narrow set of diseases. Human trials with survival endpoints would take decades. Companion dogs sit between the two: genetically diverse animals that share their owners' homes, air, water, and habits, receive medical care with diagnostics resembling human medicine, and compress an aging trajectory into ten to fifteen years. The consortium was founded by biogerontologists Daniel Promislow and Matt Kaeberlein at the University of Washington with veterinarian Kate Creevy, now chief veterinary officer at Texas A&M. It is an academic, largely federally funded effort and is separate from the commercial canine-l","c":["organizations","longevity"],"k":"organization","x":"established","h":"present","w":1133,"n":3},{"s":"dual-use-research","t":"Dual-use research of concern","d":"Life-science research that produces knowledge or tools with legitimate purposes but foreseeable potential for catastrophic misuse, and the oversight regimes built around it.","g":["biosecurity","governance","pandemics","gain of function","policy","risk"],"b":"Dual-use research of concern, or DURC, is life-science research conducted for legitimate purposes that could reasonably be anticipated to yield knowledge, methods, or materials directly applicable to causing large-scale harm. The category was formalised in US policy in the 2000s, following a National Research Council report that identified a short list of experiments of concern. It covers a narrow slice of biology: work that increases a pathogen's transmissibility, virulence, host range, or resistance to countermeasures, or that renders a dangerous agent easier to produce. The category is the clearest case in which the same result is both a public good and a hazard, and every available response is a trade-off rather than a solution. The mechanism Biological risk differs from other technological risk in three ways that shape the governance problem. The information itself carries the hazard. A method published in a journal cannot be recalled, is available identically to everyone who reads it, and does not degrade. What stands between knowledge and misuse is tacit skill and materials, and both of those barriers have fallen. Capability is dual by construction. Understanding what makes an influenza virus transmissible between mammals is the same knowledge that would allow one to be made transmissible. Surveillance, vaccine design, and countermeasure development all require it, and n","c":["society","genetics"],"k":"risk","x":"established","h":"present","w":1441,"e":"No documented case exists of published dual-use research being used to cause mass harm; the recorded human toll is from laboratory-acquired infections and containment failures.","a":"The enabling capability is widely available: gene synthesis is a commercial service and pathogen sequences are public, with order screening voluntary and incomplete.","r":"irreversible","n":27},{"s":"ectogenesis","t":"Ectogenesis","d":"The development of a mammalian embryo or fetus outside a body, either for part of gestation or for all of it, and the ethical arguments the prospect generates.","g":["reproduction","ectogenesis","bioethics","feminism","abortion","personhood"],"b":"Ectogenesis is the development of an embryo or fetus outside a body. The literature distinguishes partial ectogenesis, in which a fetus is transferred to a device part-way through gestation, from complete ectogenesis, in which fertilisation, implantation, and the whole of gestation occur outside any organism. Partial ectogenesis has been achieved in sheep and is the goal of every device programme now running. Complete ectogenesis in a mammal has never been demonstrated, and the missing step is placentation, not equipment. Origins of the term J. B. S. Haldane coined the word in a lecture given at Cambridge in 1923 and published as Daedalus; or, Science and the Future. Writing in the voice of a future undergraduate looking back, he imagined that gestation outside the body would become normal within a century and that the change would be greeted first with disgust and then with indifference. His point was less about wombs than about a pattern: every biological invention, he argued, appears blasphemous before it becomes ordinary. Aldous Huxley, who knew Haldane, took the same image and reversed its moral charge. The hatcheries of Brave New World in 1932 attached ectogenesis to a state that had abolished families. They fixed the association between artificial gestation and totalitarian control that most later fiction has reproduced. The two readings have travelled together ever sinc","c":["reproduction","society"],"k":"concept","x":"speculative","h":"2040s","w":1430,"e":"No part of human gestation has been sustained outside a body; the closest results are weeks of survival in preterm lambs and mouse embryos cultured to roughly half of gestation.","n":8},{"s":"effective-accelerationism","t":"Effective accelerationism","d":"An online techno-optimist movement holding that technological acceleration is a moral imperative and that precautionary restraint on AI causes more harm than it prevents.","g":["movements","artificial intelligence","technology policy","optimism","ai safety","internet culture"],"b":"Effective accelerationism, usually written e/acc, is a techno-optimist movement that emerged online in 2022. It holds that the development and deployment of powerful technology, Artificial general intelligence above all, should be accelerated rather than restrained, and that attempts to slow it are themselves the greater harm. Its name deliberately inverts effective altruism, the movement it defines itself against. It is better understood as a rhetorical and political formation than as a research programme: it has produced manifestos, memes and companies, but no body of theory. Overview The movement's positive claim is that technological progress is the mechanism by which human welfare has historically improved, that this mechanism is now being obstructed by a coalition of regulators and safety researchers, and that the expected cost of obstruction (lives not saved, poverty not ended, capabilities not gained) exceeds the expected cost of moving fast. Its negative claim, pressed harder and more often, is that AI-risk arguments are unfalsifiable, self-serving to the institutions that make them, and a route to regulatory capture by incumbents. Neither claim is new. Both were made in near-identical form by extropians in the 1990s, and the risk-of-inaction argument is a restatement of the proactionary principle that Max more drafted in 2004 as a counter to the Precautionary principl","c":["people","society"],"k":"concept","x":"contested","h":"present","w":1468,"n":9},{"s":"ecog-interfaces","t":"Electrocorticography interfaces","d":"Brain-computer interfaces that record from electrode arrays resting on the cortical surface rather than penetrating it, trading single-neuron resolution for stability and coverage.","g":["bci","ecog","speech decoding","neural recording","implants","epilepsy"],"b":"Electrocorticography interfaces are brain-computer interfaces that record from electrode arrays laid on the surface of the cortex, either beneath the dura (subdural) or on top of it (epidural), without penetrating brain tissue. They sit in the middle of the invasiveness range. Their spatial and spectral resolution is better than scalp electroencephalography and worse than a penetrating Utah array, and their mechanical stability is better than either. The technique exists because neurosurgery needed it first. Grids of platinum contacts have been placed on the cortex for decades to localize seizure onset and map eloquent cortex before epilepsy surgery. The field therefore inherited a large clinical base of patients temporarily instrumented with electrodes and willing to take part in research, and most of what is known about how speech is represented in human cortex comes from that population. How it works A standard clinical grid is a silicone sheet holding platinum discs a few millimetres across on a one-centimetre pitch. Research arrays go finer. High-density grids use a two to four millimetre pitch, and thin-film micro-electrocorticography arrays carry hundreds or thousands of contacts at sub-millimetre spacing on a substrate thin enough to conform to the cortical surface, including into sulci. The most useful feature for a Brain computer interface is high-gamma power, roughly","c":["cybernetics"],"k":"technology","x":"emerging","h":"late 2020s","w":1148,"e":"Almost the entire evidence base is human: epilepsy patients temporarily implanted for seizure mapping, plus single participants with paralysis or ALS who have used chronic arrays for speech, cursor and walking control.","a":"Clinical grids are cleared only for temporary use around epilepsy surgery; every chronic interface use is a small investigational study, and no chronic product is approved.","r":"difficult","n":15},{"s":"embryo-selection","t":"Embryo selection","d":"Testing embryos created by IVF and choosing which to transfer, a routine clinical practice for single-gene disease whose extension to complex traits remains disputed.","g":["reproduction","ivf","embryo selection","genomics","bioethics","screening"],"b":"Embryo selection is the practice of testing embryos created by in vitro fertilisation and choosing which ones to transfer to a uterus. It is the only form of genetic choice over offspring in routine clinical use anywhere, and it is the concrete reality behind most of what is discussed under the heading of Designer babies. What it can deliver depends almost entirely on whether a trait is determined by a single locus or by thousands, a distinction public debate consistently underweights. The four tests Preimplantation genetic testing is now named by what it looks for. The current names were standardised in the late 2010s and replaced the older PGD and PGS labels. - PGT-M, for monogenic disease. Where the parents' variants are known, embryos can be genotyped for the disease allele alongside linked markers from family members, which guards against amplification failure. Accuracy is high, and PGT-M is the uncontested core of the technique. - PGT-SR, for structural rearrangements. Carriers of balanced translocations produce a high proportion of unbalanced embryos; testing identifies them. - PGT-A, for aneuploidy. It screens for the wrong number of chromosomes, on the assumption that transferring euploid embryos raises live-birth rates. It is widely sold and the least well supported of the four. - PGT-P, for polygenic scores. It ranks embryos by predicted risk of common disease or by ","c":["reproduction","genetics"],"k":"technology","x":"established","h":"present","w":1557,"e":"In human clinical use since the first births from biopsied embryos in 1990: testing for a known single-gene variant reliably identifies affected embryos, while randomized trials of aneuploidy screening have not shown higher live-birth rates.","a":"Legal and clinically available in nearly every country with IVF, but a cycle with genetic testing costs more than most health systems will reimburse for a couple who are not infertile.","r":"irreversible","n":24},{"s":"emmanuelle-charpentier","t":"Emmanuelle Charpentier","d":"French microbiologist who identified the second RNA that CRISPR-Cas9 requires, co-authored the 2012 paper that made the system programmable, and shared the 2020 Nobel Prize in Chemistry.","g":["crispr","gene editing","rna","nobel prize","microbiology","bacteria"],"b":"Emmanuelle Charpentier is a French microbiologist who reached CRISPR from the study of bacterial disease rather than from genome engineering. Her laboratory identified tracrRNA, the second small RNA that the type II CRISPR system needs in order to work, and she then co-authored the 2012 paper showing that the system could be reduced to a protein and a single engineered guide and directed at any chosen DNA sequence. She shared the 2020 Nobel Prize in Chemistry with Jennifer doudna for that result, and has continued to run a laboratory on bacterial pathogens rather than on editing. Career Charpentier was born in Juvisy-sur-Orge, south of Paris, studied biochemistry and microbiology at the Université Pierre et Marie Curie, and completed a doctorate in 1995 on molecular mechanisms of antibiotic resistance, with the research carried out at the Institut Pasteur. She then spent six years in the United States: at Rockefeller University working on Streptococcus pneumoniae, then at NYU Medical Center, St. Jude Children's Research Hospital and the Skirball Institute. She returned to Europe in 2002 and moved repeatedly: the University of Vienna and the Max F. Perutz Laboratories from 2002, the Laboratory for Molecular Infection Medicine Sweden at Umeå University from 2008, and the Helmholtz Centre for Infection Research in Braunschweig together with Hannover Medical School from 2013. In 20","c":["people","genetics"],"k":"person","x":"established","h":"present","w":1316,"n":1},{"s":"engineered-pandemics","t":"Engineered pandemics","d":"Outbreaks caused by a pathogen deliberately modified, synthesised, or released rather than one that emerged from nature, and the biosecurity programme built around preventing them.","g":["biosecurity","pandemics","gain of function","governance","catastrophic risk","synthetic biology"],"b":"Engineered pandemics are outbreaks caused by a pathogen that has been deliberately modified, deliberately built from a published sequence, or deliberately released, rather than one that crossed into humans from an animal reservoir. No such event is known to have happened. The category is nonetheless treated as one of the more plausible routes to a global catastrophe, on structural grounds: the agent replicates on its own, the enabling knowledge is published and cannot be recalled, and the cost of the underlying techniques has fallen by orders of magnitude while the number of people able to use them has risen. What would make a pathogen pandemic-capable Natural selection optimises pathogens for transmission, not for lethality, and the two usually trade against each other: an agent that incapacitates its host quickly spreads less. Biosecurity analysts are concerned with the combinations that evolution rarely assembles and an engineer might. The standard example is long presymptomatic infectiousness paired with high case fatality. Resistance to existing vaccines and antivirals is a second, and it turns a manageable agent into an unmanageable one without changing its biology much. Whether such a combination can actually be built is not established. The demonstrated result is narrower: a specific barrier to mammalian airborne transmission can be crossed deliberately. Two laboratorie","c":["society","genetics"],"k":"risk","x":"speculative","h":"present","w":1466,"e":"No engineered pathogen has caused a pandemic; the documented toll from deliberate or accidental release runs to dozens of deaths, chiefly the 1979 Sverdlovsk anthrax escape and the 2001 anthrax letters.","a":"The enabling inputs are ordinary: pathogen sequences are published, synthetic DNA is a commercial service, and order screening is voluntary in most jurisdictions.","r":"irreversible","n":2},{"s":"sleep-reduction","t":"Engineered sleep reduction","d":"The proposal to shorten the amount of sleep a person needs without incurring the costs of sleep deprivation, based on rare short-sleep gene variants and wake-promoting drugs.","g":["sleep","enhancement","genetics","pharmacology","cognition","circadian"],"b":"Engineered sleep reduction is the proposal to lower how much sleep a person requires, rather than merely suppressing the feeling of sleepiness, so that waking hours increase without the deficits that follow sleep loss. It is one of the few enhancement targets with a natural existence proof, since a small number of families carry variants that let them sleep four to six hours a night, apparently without impairment. Whether that biology can be transferred to anyone else, and whether the apparent absence of cost survives careful measurement, are both unresolved. Sleepiness is not sleep need The distinction that organises the subject is between the drive to sleep and the functions sleep performs. Caffeine, modafinil and amphetamines act on the first. They suppress the subjective and, to a degree, the performance consequences of being awake too long, but they do not discharge the underlying pressure. The sleep that is lost is still owed, and slow-wave rebound follows when the drug wears off. A drug that removes sleepiness without removing sleep need is a stimulant rather than an enhancement. That makes the functions the real target, and they are plural. Sleep is implicated in synaptic downscaling, in memory consolidation, in metabolic and hormonal regulation, in immune function, and in clearance of interstitial waste from the brain, which ties it to the aggregation problems describe","c":["enhancement"],"k":"concept","x":"speculative","h":"2040s","w":1450,"e":"No human demonstration exists. The evidence is rare families carrying short-sleep variants, described in small pedigrees with self-report and limited cognitive testing, plus mouse models of those variants.","n":6},{"s":"enhancement-arms-race","t":"Enhancement arms race","d":"The argument that competitive pressure makes enhancement effectively compulsory, so that individually rational adoption leaves everyone worse off.","g":["enhancement","coercion","sport","military","economics","policy"],"b":"Enhancement arms race describes a situation in which the benefit of an enhancement depends on having it when others do not, so that each person's rational decision to adopt it removes the advantage while leaving everyone with the costs. The argument is the strongest objection to enhancement that does not depend on any claim about human nature, dignity, or the value of the given. It grants that the technology works, that people choose it freely, and that each choice is individually sensible, and it shows that the outcome can still be worse for everyone. Positional and absolute goods The distinction comes from Fred Hirsch, who observed that some goods are valuable in themselves and others only in relation to what others have. Clean water is absolute: everyone having it is better than some people having it. A front-row seat is positional, because its value consists in others not having it. Robert Frank extended the analysis to biological competition, noting that traits selected for relative advantage (antler size is his standing example) impose costs on every member of the population without improving any individual's rank. The modalities catalogued in Human enhancement divide along this axis, and where a modality falls determines what policy suits it. Absolute. Resistance to infection, repair of damaged tissue, freedom from pain. Universal adoption makes everyone better off, and ","c":["society","enhancement"],"k":"concept","x":"contested","h":"2030s","w":1363,"n":12},{"s":"enhancement-in-sport","t":"Enhancement in sport","d":"The regulation of performance enhancement in competition, the only domain that draws an operational line between therapy and enhancement and litigates it case by case.","g":["sport","doping","regulation","fairness","prosthetics","eligibility"],"b":"Enhancement in sport is the use of substances, methods and equipment to raise athletic performance, and the regulatory apparatus built to prohibit some of it. Sport is unusual among human activities in maintaining a formal, enforced boundary between restoring health and exceeding it, complete with a list of banned agents, a testing infrastructure, an appeals court, and a procedure for granting exemptions. That machinery makes it the best available case study for what happens when the therapy-enhancement distinction described in Human enhancement is turned into administrative law. The regime Anti-doping predates the World Anti-Doping Agency by decades, but the modern system dates from the 1998 Tour de France, when a team car full of doping products was intercepted and the resulting scandal made clear that federations could not police themselves. WADA was established the following year as a joint initiative of the Olympic movement and governments, and the World Anti-Doping Code came into force in 2004. It has been revised several times since. Its central features are an annually revised Prohibited List, accredited laboratories, out-of-competition testing with whereabouts requirements, and strict liability: an athlete is responsible for what is in their body regardless of intent, subject to reduced sanction where fault is minimal. That provision governs the recurring disputes over","c":["enhancement","society"],"k":"concept","x":"established","h":"present","w":1599,"n":19},{"s":"epigenetic-clock","t":"Epigenetic clocks","d":"Statistical predictors that estimate age or mortality risk from DNA methylation patterns at selected sites in the genome.","g":["epigenetics","biomarkers","aging","dna methylation","measurement"],"b":"Epigenetic clocks are statistical models that estimate a person's age, or their risk of death, from the pattern of methyl groups attached to cytosines at selected positions in their genome. They are the most widely used molecular measure in aging research: cheap enough to run on stored blood or saliva, and startlingly accurate at predicting chronological age. What they measure biologically, and whether moving a clock reading means anything, are open questions. What a clock measures DNA methylation at CpG dinucleotides regulates gene expression and differs systematically between tissues and between young and old individuals. A clock is built by taking methylation values at hundreds of thousands of sites, measured on a commercial array, and fitting a penalised regression that predicts a target variable from a small subset of them. The selected sites do not amount to a mechanism; they are whichever coordinates carried the most predictive signal in the training data. For a clock trained on chronological age, the informative quantity is the residual, the difference between predicted and actual age, usually called epigenetic age acceleration. A person whose blood reads five years older than their birth certificate is, on average across large cohorts, at somewhat elevated risk of death and of several chronic diseases. The effect is real but modest. Compared with earlier candidate meas","c":["longevity"],"k":"technology","x":"established","h":"present","w":1542,"e":"Built and validated in large human cohorts, where age acceleration predicts mortality and disease modestly; no trial has shown that moving a clock reading changes an outcome.","a":"Sold direct to consumer as mail-in methylation tests and available as a research assay on standard arrays; no clock is an approved clinical test or an accepted regulatory endpoint.","r":"reversible","n":54},{"s":"epigenetic-reprogramming","t":"Epigenetic reprogramming","d":"The use of pluripotency factors to reset age-associated marks on DNA and chromatin, restoring youthful gene expression in cells without converting them into stem cells.","g":["reprogramming","epigenetics","rejuvenation","gene therapy","aging","stem cells"],"b":"Epigenetic reprogramming is the deliberate resetting of the chemical marks on DNA and histones that determine which genes a cell expresses. Applied briefly, it restores several youthful molecular features in old cells and old animals without turning them into stem cells; applied for too long, it erases cell identity and produces tumours. The narrow window between rejuvenation and dedifferentiation is the central technical problem of the field, and no one has yet shown that a treatment can be kept inside it in a human being. The epigenetic view of aging Every cell in a body carries nearly the same genome but reads a different portion of it. Which portion is set by cytosine methylation, histone modification, chromatin accessibility, and the transcription-factor networks that maintain them. These patterns drift with age in ways that are reproducible enough to be read as a clock: methylation at a few hundred sites predicts chronological age across tissues to within a few years, which is the basis of the epigenetic clocks. The drift is structured. Across mammals, CpG islands controlling developmental genes, many of them targets of the polycomb repressive complexes, gain methylation with age, while the genome as a whole loses it. Heterochromatin at repetitive regions relaxes. Chromatin that should be closed in a given cell type opens, and lineage-inappropriate genes become detectably","c":["longevity","genetics"],"k":"technology","x":"experimental","h":"2030s","w":1751,"e":"No person has been treated with reprogramming as a rejuvenation therapy: those results are from mice or cultured human cells, where transient reprogramming lowered methylation age without loss of fibroblast identity. Full reprogramming to iPSCs is separate.","a":"Nothing to obtain outside the laboratory; no partial-reprogramming therapy has published clinical data, and companies have so far stated only an intention to file for first-in-human trials.","r":"context","n":30},{"s":"epigenome-editing","t":"Epigenome editing","d":"Targeted modification of the chemical marks that control gene expression, switching a gene off or on without altering the underlying DNA sequence.","g":["crispr","epigenetics","gene regulation","gene therapy","dna methylation","biotechnology"],"b":"Epigenome editing changes how much of a gene a cell makes without changing the gene itself. A programmable DNA-binding protein is aimed at a promoter or enhancer and carries with it an enzyme that writes or erases a regulatory mark (DNA methylation, histone modification) or that simply recruits the cell's own repression machinery. The sequence is left intact, which means the change is in principle reversible, and which also means it can be lost. That distinguishes it sharply from Base editing and Prime editing, which alter the genome permanently and cannot be undone once installed. How it works Every epigenome editor is two interchangeable halves bolted together: something that finds a chosen stretch of DNA, and something that acts on the chromatin once it arrives. The halves are developed independently, which is why advances in targeting from nuclease work transfer directly to this field. The DNA-binding module The most common targeting scaffold is catalytically dead Cas9, produced by disabling both nuclease domains of the enzyme described in Crispr cas9. It retains full guide-RNA-programmed binding and none of the cutting. Zinc-finger proteins and TALE arrays, the platforms that preceded CRISPR, remain in use for the same purpose and have two advantages for therapy: they are considerably smaller, which eases packaging, and being closer to human protein scaffolds they may prov","c":["genetics"],"k":"technology","x":"experimental","h":"2030s","w":1287,"e":"Early-phase trials in chronic hepatitis B and facioscapulohumeral muscular dystrophy are reported to have dosed patients in 2024 and 2025, with no published results; the year-long silencing results are from mice.","a":"Not obtainable outside company-run clinical trials; no epigenetic editor has been approved by any regulator.","r":"context","n":14},{"s":"eric-drexler","t":"Eric Drexler","d":"American engineer who proposed molecular nanotechnology, wrote Engines of Creation and Nanosystems, and later worked on AI strategy at Oxford.","g":["nanotechnology","molecular manufacturing","grey goo","foresight","artificial intelligence"],"b":"Eric Drexler is an American engineer and theorist who argued that mechanical control of chemical synthesis at the molecular scale is physically permitted, and that a technology built on it would allow manufacturing with atomic precision. His 1986 book Engines of Creation introduced molecular nanotechnology to a general audience along with the Grey goo scenario; his 1992 technical treatise Nanosystems attempted to establish the physical case. Neither the machines nor the catastrophe has materialized, and the argument over why has defined his career. Career Drexler studied at MIT, initially working on space systems including solar sails, and completed a doctorate there in 1991 under Marvin Minsky at the Media Lab, the first doctorate awarded in molecular nanotechnology. His first technical publication on the subject appeared a decade earlier, proposing that protein engineering could bootstrap a route to general molecular machinery. With Christine Peterson he co-founded the Foresight Institute in 1986 to promote and monitor the field. After the American nanotechnology programme moved decisively away from his agenda, he shifted focus. He joined the Future of Humanity Institute at Oxford as a research fellow, working with Nick bostrom and Anders sandberg on technology strategy and, latterly, on artificial intelligence. Molecular nanotechnology The core claim of Nanosystems is mechan","c":["people","nanomedicine"],"k":"person","x":"contested","h":"present","w":1145,"n":11},{"s":"exercise-and-aging","t":"Exercise as a geroprotector","d":"Structured physical activity, the intervention with the strongest evidence for extending healthy life in humans and the benchmark any geroprotective drug must beat.","g":["exercise","cardiorespiratory fitness","sarcopenia","aging","healthspan","clinical trials"],"b":"Exercise as a geroprotector is the proposition that structured physical activity acts on the underlying biology of aging rather than only on the fitness of the individual muscles and vessels trained. It has better human evidence than any drug in geroscience, including randomized trials with functional endpoints, and it is the comparator against which every candidate geroprotective compound is implicitly measured. Its limits are equally clear: it has not been shown to extend maximum lifespan in laboratory rodents, and adherence, not efficacy, is the binding constraint in practice. The evidence The observational base is unusually large and unusually consistent. Pooled cohort analyses associate leisure-time activity at guideline levels with a gain in life expectancy on the order of three to four years. In a retrospective study of more than a hundred thousand patients referred for treadmill testing, all-cause mortality fell steadily as measured cardiorespiratory fitness rose, with no observed level beyond which additional fitness ceased to help. Grip strength, a cheap proxy for whole-body muscle function, predicts all-cause and cardiovascular mortality across countries and income levels. Observational data on exercise carry a specific hazard: people become sedentary because they are ill, so low activity can be a symptom rather than a cause. What distinguishes exercise from most ger","c":["longevity"],"k":"intervention","x":"established","h":"present","w":1098,"e":"A randomized trial in sedentary adults aged 70 to 89 lowered incident mobility disability, and large human cohorts link fitness to lower mortality; no trial has tested lifespan.","a":"Freely available and close to costless: guideline-level activity requires no prescription, and adherence rather than price or supply is the binding constraint.","r":"reversible","n":48},{"s":"existential-risk","t":"Existential risk","d":"The category of risks that would end humanity or permanently destroy its potential, and the research programme built around identifying and reducing them.","g":["risk","governance","biosecurity","longtermism","forecasting","policy"],"b":"Existential risk is a risk of an outcome that would either annihilate Earth-originating intelligent life or permanently and drastically curtail its potential. The definition is Nick bostrom's, from a 2002 paper that gave the field its name, and what distinguishes the category is irreversibility rather than severity. In this framework a catastrophe that kills a large fraction of humanity, but from which the survivors recover, is categorically different from one that forecloses the future, however similar the two look in the immediate aftermath. The definition and its taxonomy Bostrom's original classification sorted outcomes by how the potential is lost. Bangs are sudden extinction events. Crunches leave humanity alive but permanently unable to develop further. Shrieks reach a form of posthuman existence realising only a fraction of what was possible. Whimpers are gradual erosions. A later restatement replaced the taxonomy with two axes, scope and severity, and placed existential risk in the far corner of both. Treating a permanent curtailment of potential as equivalent to extinction requires the view that the value at stake lies mostly in the future rather than the present. That premise connects this research to longtermism, and many critics reject it. The related term global catastrophic risk is broader and does not require irreversibility. The mechanism A risk is existential ","c":["society","foundations"],"k":"risk","x":"contested","h":"indefinite","w":1588,"e":"No existential catastrophe has occurred, so the anthropogenic probabilities are stated credences rather than estimates from data; only the natural background rate is bounded, by the fossil and geological record.","r":"irreversible","n":29},{"s":"extropianism","t":"Extropianism","d":"The first organized transhumanist movement, built around a set of optimistic principles for self-directed human transformation and dissolved as an institution in 2006.","g":["transhumanism","movements","libertarianism","extropy","intellectual history","mailing lists"],"b":"Extropianism is the first organized transhumanist movement, formulated in California in the late 1980s around a set of principles favouring perpetual self-improvement, rational optimism, decentralized order, and the deliberate use of technology to overcome biological limits. Its institutional life was short (the Extropy Institute closed in 2006), but its mailing list incubated ideas and people that went on to shape AI risk research, cryptocurrency, and the modern longevity industry. The name \"Extropy\" was coined as an informal antonym of entropy: a measure of a system's intelligence, functional order, vitality, and capacity for improvement. Its authors stated explicitly that it is not a physical quantity and not measurable, and warned against treating it as one. The term served as a banner rather than a concept: it signalled that the movement was oriented toward growth and organization in a universe that tends the other way. Origins Max More, then a philosophy graduate student who had changed his name from Max O'Connor, and Tom Bell, writing as T. O. Morrow, launched Extropy: The Journal of Transhumanist Thought in 1988. Its early issues collected material on Cryonics, nanotechnology as Eric drexler had described it, Nootropics, space settlement, artificial intelligence, and libertarian political economy. These had existed as scattered enthusiasms but had not previously been gi","c":["people"],"k":"concept","x":"historical","h":"historical","w":1221,"n":12},{"s":"face-and-hand-transplantation","t":"Face and hand transplantation","d":"The transplantation of a donor's face, hand or arm as one living unit of skin, muscle, bone, nerve and vessel, a graft that improves a life rather than saving it.","g":["transplantation","immunology","immunosuppression","surgery","amputation","prosthetics","identity","bioethics"],"b":"Face and hand transplantation is the surgical transfer of a face, hand or arm from a donor to a person who has lost their own to injury or disease, with the graft's blood vessels, nerves and supporting tissues joined to the recipient's. Both belong to a class of procedures called vascularized composite allotransplantation (VCA): vascularized because the graft survives only if its arteries and veins are connected to the recipient's circulation, composite because it contains several kinds of tissue moved as one anatomical unit, and allotransplantation because donor and recipient are different people. The graft keeps no one alive, yet it needs lifelong immunosuppression, as a kidney or heart does, and that exchange of risk for quality of life has generated much of the ethical debate about it. By the end of 2024, 53 face transplants and about 151 hand transplants had been performed worldwide. What is transplanted When the United States brought these grafts under its organ transplant rules, it defined them by behaviour rather than anatomy. A VCA needs its blood vessels surgically connected, contains several tissue types, is transplanted as an anatomical unit, does the same job in the recipient as in the donor, and is not combined with a device. It tolerates only brief storage and is liable to rejection, so it generally requires immunosuppression. The rule named faces, limbs, larynge","c":["bodies","society"],"k":"intervention","x":"emerging","h":"present","w":2599,"e":"About 53 face and 151 hand transplants were reported worldwide by the end of 2024, in case reports, registries and cohort reviews with no randomized trials; most grafts survive for years, but most recipients have rejection episodes.","a":"Offered at a small number of specialist centres, mostly under research protocols; US insurers do not cover it, so grants, philanthropy and hospitals pay; a Leeds service offers hand transplants as standard care.","r":"difficult","n":3},{"s":"fm-2030","t":"FM-2030","d":"Iranian-American futurist, born Fereidoun M. Esfandiary, who defined the transhuman as a transitional being and was cryopreserved on his death in 2000.","g":["transhumanism","futurism","cryonics","identity","life extension"],"b":"FM-2030 was an Iranian-American futurist, novelist and teacher, born Fereidoun M. Esfandiary. He argued that some people alive in the twentieth century were already transitional beings, no longer fully bound by the biological, national and family categories that had defined human life and not yet whatever comes next. He called such people transhumans, and the usage passed into Transhumanism as a movement. He replaced the name he was born with by FM-2030, which points at the year he would turn one hundred. Life Esfandiary was born in Brussels in October 1930 to Iranian diplomats and spent his childhood moving between postings in Europe and Asia; biographical accounts repeat his claim to have lived in seventeen countries as a child. He played basketball for Iran at the 1948 Olympic Games in London, and from 1952 to 1954 served on the United Nations Conciliation Commission for Palestine. Early rootlessness and direct exposure to the machinery of international institutions shaped his lifelong argument that national and ethnic identity was a residue rather than a fact. He published three novels in English: The Day of Sacrifice (1959), The Beggar (1965) and Identity Card (1966), the last a study of bureaucratic identity in Iran. From the late 1960s he turned to futurism, teaching long-running courses on the future at The New School in New York, at UCLA Extension and later at Florida ","c":["people"],"k":"person","x":"historical","h":"historical","w":1215,"n":6},{"s":"future-of-humanity","t":"Future of humanity","d":"The study of humanity's possible long-run trajectories, conventionally grouped into extinction, recurrent collapse, plateau, and posthuman transformation.","g":["forecasting","existential risk","longtermism","demography","trajectories","philosophy"],"b":"Future of humanity names the attempt to reason systematically about which long-run trajectories are open to the human species and its descendants, and how likely each is. It is not forecasting in the ordinary sense: the events at issue are unprecedented, the relevant timescales exceed any dataset, and the most consequential variables are the least predictable. What the field offers instead is a discipline of constraint: physical limits that no technology can exceed, historical base rates that any specific claim must beat, and a taxonomy that keeps arguments from talking past each other. Four trajectories Nick bostrom's 2009 essay set out the taxonomy the field still uses. Every long-run scenario, he argued, falls into one of four families, distinguished by where the trajectory ends up rather than by how it gets there. Extinction. Humanity ceases to exist, permanently. The category includes both sudden events and slow declines, and its defining feature is irreversibility: unlike every other outcome, it forecloses all subsequent ones. Derek Parfit's argument that the moral difference between near-extinction and extinction is far larger than the difference in immediate casualties turns on exactly this asymmetry. Recurrent collapse. Civilisation repeatedly reaches roughly its present level of technology and repeatedly falls back, without either dying out or advancing further. This ","c":["foundations","society"],"k":"concept","x":"speculative","h":"indefinite","w":1939,"n":12},{"s":"gene-doping","t":"Gene doping","d":"The non-therapeutic use of gene transfer or gene regulation to improve athletic performance, prohibited in sport since the early 2000s with no publicly confirmed case.","g":["sport","enhancement","gene therapy","doping","detection","regulation"],"b":"Gene doping is the use of gene transfer, gene editing or gene regulation to improve athletic performance rather than to treat disease. It has been prohibited in competitive sport since the early 2000s, before any technique for doing it existed, and it remains prohibited today. No case has been publicly confirmed in an elite athlete. The subject is defined by that gap between a prohibition written in anticipation and an offence nobody has proved. The targets The candidate genes come from exercise physiology and from muscle-disease research, where the same constructs are studied as therapies. Erythropoietin. EPO drives red-cell production and therefore oxygen delivery. Recombinant EPO is the classic endurance drug, and a gene-transfer version would in principle produce it endogenously and continuously. That constancy is also the main hazard, since expression from a viral vector cannot easily be turned down. Myostatin and its antagonists. Blocking myostatin increases muscle mass, an effect established in cattle, dogs and mice, and pursued clinically for muscle-wasting disease. Follistatin constructs delivered by adeno-associated virus are the most plausible muscle-directed doping agent, because they have already been administered to humans outside clinical trials. The biology and its disappointments are set out in Myostatin inhibition. IGF-1. Local delivery of insulin-like growth ","c":["enhancement","genetics"],"k":"concept","x":"experimental","h":"late 2020s","w":1364,"n":10},{"s":"gene-drive","t":"Gene drives","d":"Genetic elements engineered to bias their own inheritance above the Mendelian half, allowing an introduced trait to spread through a wild population.","g":["crispr","malaria","ecology","biosafety","governance","mosquitoes"],"b":"Gene drives are genetic elements that copy themselves into the matching chromosome in the germline, so that a heterozygous parent passes the element to far more than half of its offspring. An engineered drive can therefore spread through a wild population from a small release, in principle carrying a trait to fixation against natural selection. The idea long predates Crispr cas9, but the ability to program a nuclease with an RNA guide is what made building one straightforward, and what turned a theoretical proposal into a governance problem. How it works A standard homing drive consists of a nuclease, a guide RNA that specifies a site in the host genome, and the whole cassette inserted at that same site. In a heterozygote, the drive-bearing chromosome expresses the nuclease, which cuts the corresponding site on the intact homologous chromosome. If the cell repairs that break by homologous recombination, it uses the drive-bearing chromosome as template and copies the entire cassette across. The organism, formerly heterozygous, is now homozygous, and every gamete carries the drive. The two useful designs differ in what they carry. Population modification drives spread a cargo that makes the organism harmless (in mosquitoes, an effector that blocks development of the malaria parasite) while leaving the population intact. Population suppression drives target a gene required for fem","c":["genetics","society"],"k":"technology","x":"experimental","h":"2030s","w":1548,"e":"No drive-carrying organism has been released anywhere as of 2026, so the human outcome claimed for the technology, reduced malaria transmission, is untested; every suppression result comes from caged mosquito populations.","a":"Nothing to obtain: drives exist only in contained laboratory and cage colonies, and no regulator anywhere has authorised a field release.","r":"irreversible","n":19},{"s":"gene-therapy-for-aging","t":"Gene therapy for aging","d":"The use of delivered genes to modify aging biology systemically, demonstrated in mice with telomerase and other constructs and untested in any controlled human trial.","g":["gene therapy","aav","telomerase","klotho","follistatin","aging","self-experimentation"],"b":"Gene therapy for aging is the delivery of genetic material to a large fraction of an adult's cells with the aim of changing the trajectory of aging itself rather than treating a single inherited disease. The methods are those of ordinary Somatic gene therapy; the ambition is larger. The same viral vectors and nucleic-acid payloads are aimed at systemic targets such as telomere maintenance, muscle mass, or epigenetic state, and given to people who are not sick by any current definition. As of 2026 the animal results are real, and the human record consists almost entirely of unregulated self-experimentation. The animal evidence The founding result came from telomerase. A 2012 study delivered the mouse TERT gene in an adeno-associated viral vector to adult mice and reported extended median lifespan, with a larger effect in animals treated at one year of age than at two, and without an observed increase in cancer incidence. The lack of an observed cancer increase is the surprising part, because telomerase reactivation is a near-universal feature of tumours, and the finding has not been reproduced widely enough to settle the safety question. How much it means depends on the broader argument covered under Telomeres and telomerase: in several respects telomere attrition is a weaker driver of human aging than of mouse aging. Two other targets recur. Klotho, a protein whose loss in mice","c":["longevity","genetics"],"k":"intervention","x":"experimental","h":"2040s","w":1429,"e":"No controlled trial has tested any of these constructs against aging in people; the human record is self-administration and single-arm offshore studies without published results, plus early-phase trials in muscle and eye disease.","a":"Not approved for any aging indication; offshore ventures have charged for unapproved telomerase and follistatin constructs at reported prices from about $25,000 to $1 million per dose.","r":"context","n":31},{"s":"generation-ship-biology","t":"Generation ship biology","d":"The biological requirements of a crewed voyage lasting generations: population genetics, reproduction and development off Earth, and consent for people born in transit.","g":["interstellar","population genetics","reproduction","closed ecology","consent","spaceflight"],"b":"Generation ship biology is the study of what a crewed interstellar voyage would require of human biology when the voyage outlasts the people who begin it. The engineering problems of such a ship, including propulsion, shielding, and structure, are severe but conventionally analysable. The biological problems are of another kind. They involve a human population small enough to lose genetic diversity, a reproductive process never tested off Earth, an ecosystem with no external buffer, and several generations of people born into a mission they did not choose. Minimum viable population The starting question is how many people are needed to avoid genetic collapse. Conservation biology supplies the traditional heuristic: an effective population of about 50 avoids severe short-term inbreeding depression, while about 500 is needed to retain enough variation for long-term adaptive potential. Later analyses argued that both figures should be raised substantially. All of them refer to effective population size, which in a real group with unequal reproduction is considerably smaller than the headcount. Explicit modelling of interstellar crews has produced numbers in the same range. Monte Carlo simulations of a multi-thousand-year voyage found that a founding group on the order of a hundred could remain genetically viable under strict pairing rules that minimise relatedness, and that severa","c":["space","reproduction"],"k":"concept","x":"speculative","h":"indefinite","w":1527,"e":"No human has been conceived, gestated, or born beyond Earth, and no agency has studied conception in flight; the mammalian record is mouse embryos cultured in orbit and rodents flown during part of gestation.","n":7},{"s":"recoded-organisms","t":"Genetic code expansion and recoding","d":"Altering how a cell reads DNA so that reassigned codons encode amino acids not found in nature, producing organisms with chemistry and immunity no natural cell has.","g":["synthetic biology","genetic code","protein engineering","biocontainment","virus resistance"],"b":"Genetic code expansion and recoding are two halves of one project: changing the rules by which a cell translates DNA into protein. Expansion adds a new amino acid to an organism's repertoire by assigning it a codon; recoding clears that codon first, by replacing every natural instance of it across the genome and deleting the machinery that reads it. The result is a cell that builds proteins from a chemistry unavailable to any natural organism, and, as a side effect that has proved at least as interesting, one that viruses cannot read. How it works Changing the genetic code means changing two things that normally match: the meaning a cell assigns to a codon, and the sequences written in the old meaning. Expansion handles the first and is comparatively easy. Recoding handles the second and is the reason the field depends on genome-scale DNA synthesis. Orthogonal translation Protein synthesis assigns amino acids to codons through aminoacyl-tRNA synthetases, each of which charges a particular transfer RNA with a particular amino acid. To add a twenty-first amino acid, an engineer supplies a synthetase-tRNA pair that ignores, and is ignored by, everything already in the cell: an orthogonal pair. The synthetase is then evolved in the laboratory to accept the desired non-standard amino acid, and the tRNA is given an anticodon matching whichever codon has been set aside. The first such","c":["genetics"],"k":"technology","x":"experimental","h":"2040s","w":1374,"e":"No recoded mammal or person exists; genome recoding has been demonstrated only in bacteria, and the nearest contact with patients is investigational antibody conjugates built using non-standard amino acids.","a":"Not a clinical or consumer technology: recoded strains exist in a handful of academic laboratories, and the only products near patients are investigational antibody conjugates.","r":"irreversible","n":16},{"s":"genetic-discrimination","t":"Genetic discrimination","d":"Differential treatment of people on the basis of genetic information, and the uneven legal regime that restricts it in employment and health cover but rarely elsewhere.","g":["law","privacy","insurance","employment","gina","genomics"],"b":"Genetic discrimination is the use of a person's genetic information, such as a test result, a family history, or a predicted risk, to treat them less favourably in insurance, employment, education, or another domain where the information is not relevant to present ability. The concern predates cheap genome sequencing. It has produced a patchwork of protections that is strongest where the risk was anticipated and weakest where the information is now actually used. What is being protected The canonical case is a person who learns they carry a pathogenic variant for a late-onset condition and is then refused cover or employment on the strength of a prediction about a future they have not yet reached. Huntington's disease is the standard example, because penetrance is near total and onset is decades away. The harm has two parts. One is the adverse decision. The other is the chilling effect, in which people who fear the consequences decline testing that would benefit them clinically; surveys of at-risk families find this effect most consistently. The same reluctance could extend to predictive tests that are not genetic at all, including the direct-to-consumer panels covered in Consumer blood testing and the multi-cancer screening assays described in Nanoparticle diagnostics, where a positive result may reach an underwriter long before it becomes a diagnosis. Whether genetic informat","c":["society","genetics"],"k":"concept","x":"established","h":"present","w":1535,"n":17},{"s":"genetic-enhancement-of-intelligence","t":"Genetic enhancement of cognition","d":"The proposal to raise human cognitive ability by selecting or editing genetic variants, constrained by the extreme polygenicity of the trait and by pleiotropy.","g":["cognition","polygenic scores","gwas","enhancement","genomics","heritability"],"b":"Genetic enhancement of cognition is the proposal to raise human cognitive ability by choosing or altering genetic variants, either by selecting among embryos or by editing them. Cognitive ability is substantially heritable, which makes the proposal seem tractable, and it is also among the most polygenic traits ever mapped, which makes it intractable in practice. The distance between those two facts accounts for most of the disagreement about whether the idea is a near-term prospect or a category error. What the genetics shows Twin, adoption and family studies place the heritability of adult cognitive test performance somewhere in the range of one half to four fifths, rising through childhood into adulthood. Heritability estimated from measured common variants is considerably lower, on the order of a fifth to a quarter, and the polygenic scores built from those variants explain less again. The largest relevant studies target educational attainment, a proxy that is cheap to collect at biobank scale. A study of about three million individuals produced a score explaining something in the region of twelve to sixteen per cent of the variance in years of schooling in independent samples. Direct genome-wide studies of measured intelligence are smaller and identify hundreds of loci. In both cases the individual variants are minuscule, with the largest common-variant effects correspondin","c":["enhancement","genetics"],"k":"concept","x":"speculative","h":"2040s","w":1670,"e":"No human has been genetically enhanced for cognition; the human data are polygenic scores whose accuracy between siblings, the comparison an embryo choice actually faces, is well below their accuracy across strangers.","n":18},{"s":"george-church","t":"George Church","d":"American geneticist who helped invent direct genomic sequencing, founded the Personal Genome Project, and co-founded dozens of biotechnology companies.","g":["genomics","synthetic biology","gene editing","de-extinction","xenotransplantation","sequencing"],"b":"George Church is an American geneticist whose laboratory at Harvard Medical School has produced foundational methods in DNA sequencing, multiplexed genome engineering and genome recoding, and whose alumni and spin-out companies occupy much of contemporary synthetic biology. He is unusual among senior scientists in treating publicly provocative projects as legitimate research programmes rather than thought experiments: reversing extinction, editing pigs for human transplant, and writing data into living genomes. Career Church was dismissed from a doctoral programme at Duke in the 1970s after neglecting coursework in favour of crystallography, and completed his PhD at Harvard in 1984 with Walter Gilbert. His thesis work introduced direct genomic sequencing and multiplexed approaches that anticipated later high-throughput methods. He attended the 1984 meeting in Alta, Utah, that first seriously discussed sequencing the human genome, and has been involved in genome-scale projects ever since. He is professor of genetics at Harvard Medical School and a core faculty member of the Wyss Institute. He has spoken publicly about narcolepsy and dyslexia and has credited both with shaping how he works. Narcolepsy, he has said, made conventional deadlines unworkable, and dyslexia pushed him toward spatial and structural reasoning. Key contributions Sequencing and reading genomes Church's labo","c":["people","genetics"],"k":"person","x":"established","h":"present","w":936,"n":11},{"s":"geroscience-hypothesis","t":"Geroscience hypothesis","d":"The proposition that aging is the shared upstream driver of most chronic disease, so that slowing it would delay many conditions at once instead of one at a time.","g":["aging","chronic disease","clinical trials","regulation","biogerontology"],"b":"Geroscience hypothesis is the proposition that biological aging is the principal upstream driver of most chronic disease, and that an intervention slowing aging would therefore delay cancer, cardiovascular disease, dementia, diabetes and frailty together. It moves the target of medicine from individual pathologies to the process that makes all of them likely. The animal evidence for it is substantial; the human evidence is almost entirely absent. The argument Adult mortality risk rises roughly exponentially with age, doubling every seven to eight years, and the incidence curves for most chronic diseases follow it closely. A seventy-year-old is more likely than a thirty-year-old to have cancer, and also more likely to have heart disease, dementia, kidney disease and osteoporosis, and to have several at once. The geroscience argument reads this covariance as evidence of a common cause. Competing-risk arithmetic supplies the practical motivation. An older person who avoids one fatal disease usually dies of another, so eliminating any single disease adds surprisingly little to population life expectancy: removing all cancer deaths would add roughly three years at birth by standard estimates. An intervention that shifted the entire aging trajectory would instead push every curve to the right at the same time. Why the framing changes what gets funded Under the disease-by-disease mode","c":["longevity","foundations"],"k":"concept","x":"emerging","h":"2030s","w":1190,"e":"No randomised trial has shown that any intervention slows human aging; the human support is observational, from long-lived families and from an Ecuadorian Laron cohort with less cancer and diabetes but no longer life.","n":69},{"s":"glp-1-receptor-agonists","t":"GLP-1 receptor agonists","d":"Drugs that mimic the gut hormone GLP-1 to lower blood glucose and food intake, producing large weight loss that persists only while treatment continues.","g":["obesity","incretins","diabetes","clinical trials","metabolic health","drug access"],"b":"GLP-1 receptor agonists are drugs that activate the receptor for glucagon-like peptide-1, a hormone released by the gut after a meal; most are engineered peptides rebuilt to survive in the bloodstream for days rather than minutes. They lower blood glucose, slow gastric emptying, and act on brainstem and hypothalamic circuits to reduce food intake, and in adults with obesity the newer agents produce weight loss that no earlier drug approached. Whether that makes them a longevity intervention is the argument this article is about: they demonstrably treat conditions that shorten life, and nothing shows that they change the rate at which anyone ages. How they work GLP-1 is secreted by enteroendocrine cells lining the distal small intestine and colon when nutrients arrive. It amplifies insulin release in a glucose-dependent way, which is why these drugs rarely cause hypoglycaemia on their own; it suppresses glucagon; it slows gastric emptying; and it binds receptors in the hypothalamus and the area postrema, where the signal registers as satiety. The native peptide is destroyed within a few minutes by the enzyme DPP-4, so the problem for drug developers was how to make the hormone last. Two solutions have prevailed. The first came from a lizard: exendin-4, isolated from Gila monster venom, is naturally resistant to DPP-4 and activates the human receptor, and became exenatide. The se","c":["longevity","society"],"k":"intervention","x":"established","h":"present","w":2412,"e":"Randomized trials in tens of thousands of adults show sustained weight loss and fewer cardiovascular events in people with overweight or obesity and established heart disease; no human trial has tested lifespan.","a":"Approved and widely prescribed in most high-income countries; payer coverage is heavily restricted, US list prices are on the order of $1,000 a month beside cheaper self-pay and a $50 Medicare pilot copay, and India has had generic semaglutide since 2026.","r":"reversible","n":19},{"s":"glymphatic-system","t":"Glymphatic system","d":"A proposed brain-wide waste-clearance route in which cerebrospinal fluid enters along arteries, mixes with interstitial fluid and drains away, shown in mice and disputed in mechanism.","g":["sleep","neuroscience","dementia","neurodegeneration","amyloid","neuromodulation","brain"],"b":"The glymphatic system is a proposed pathway by which the brain clears soluble waste despite having no conventional lymphatic vessels in its tissue. In the model, cerebrospinal fluid (CSF) flows into the brain along the spaces that surround arteries, exchanges with the interstitial fluid between cells, and leaves along routes that drain towards lymph nodes in the neck. The name was coined in 2012 for a mechanism said to depend on water channels in astrocytes, a kind of glial cell. That CSF enters brain tissue along blood vessels is well supported in rodents; whether fluid actually flows through the tissue, and whether sleep speeds it up, remain disputed as of October 2026. Origins The 2012 study that named the pathway imaged small fluorescent tracers in the brains of living mice. It reported that CSF enters brain tissue along spaces surrounding penetrating arteries and that interstitial fluid leaves along spaces around veins. Mice lacking the water channel aquaporin-4 (AQP4) showed slower CSF influx and roughly a 70% reduction in interstitial solute clearance, and they cleared injected soluble amyloid-β less well. The authors proposed the name \"in light of its dependence on glial water flux, and its subservience of a lymphatic function\", making the pathway a candidate route for removing the proteins that accumulate in Alzheimers disease. A year later the same group reported that","c":["longevity","cybernetics"],"k":"concept","x":"contested","h":"indefinite","w":1604,"e":"Contrast MRI shows tracer reaching the whole human brain and clearing more slowly after a sleepless night, and fMRI links CSF pulses to NREM slow waves; no study has shown that altering the pathway changes disease in people.","n":3},{"s":"governance-of-genome-editing","t":"Governance of human genome editing","d":"The patchwork of national law, professional norms, funding rules, and international soft law that determines what may be done to a human genome and by whom.","g":["governance","regulation","bioethics","crispr","law","who"],"b":"Governance of human genome editing refers to the assembled rules (statutes, licensing regimes, funding conditions, professional statements, and international declarations) that determine which genetic interventions in humans may be attempted, by whom, and under what oversight. There is no global authority and no binding international instrument of general application. What exists instead is a patchwork. Its strongest layer is domestic criminal and medical law, its most visible layer is professional self-regulation, and it is weakest against anyone unwilling to be bound by either. The layers Four distinct mechanisms operate, and they are often confused with one another. Product regulation governs Somatic gene therapy exactly as it governs any other medicine. In the United States a gene therapy is a biological product requiring a licence; in the European Union it is an advanced therapy medicinal product. Trials require authorisation, manufacturing requires inspection, and approved products such as Casgevy carry long-term follow-up obligations, in some cases running to fifteen years. This layer is mature and works about as well as drug regulation generally does. Funding conditions shape what research happens without prohibiting anything. The US Dickey-Wicker Amendment, in force since 1996, bars federal money from research in which human embryos are created for research purposes or","c":["society","genetics"],"k":"concept","x":"emerging","h":"present","w":1424,"n":34},{"s":"grey-goo","t":"Grey goo","d":"The scenario in which self-replicating nanomachines consume the biosphere, an idea introduced by Eric Drexler in 1986 and later disowned by him.","g":["nanotechnology","existential risk","self-replication","governance","drexler","biosafety"],"b":"Grey goo is a hypothetical catastrophe in which self-replicating nanoscale machines escape control, consume available matter to make copies of themselves, and destroy the biosphere in the process. The scenario appeared in Eric drexler's Engines of Creation in 1986 as a warning attached to his proposal for molecular assemblers. It became the dominant public image of nanotechnology risk for two decades, shaped early regulatory debate, and was subsequently disowned by the person who named it. Overview Drexler's argument was structural. If assemblers can build atomically precise machinery, and if the fastest route to macroscopic quantities of product is machines that build copies of themselves, then the technology's core capability is self-replication, and self-replication with a mutation or a design error is a runaway process. He devoted a chapter of Engines of Creation to the hazard, alongside the misuse of the same technology by states. The scenario is a genuine argument rather than a throwaway image, and it has an obvious biological analogue. It differs from an ordinary invasive-species problem in the claimed generality of the eating, since a machine that can disassemble arbitrary matter into feedstock is not restricted to a niche. The link to medicine is direct. The therapeutic devices catalogued in Medical nanorobots, from the respirocyte onward, were to be manufactured by th","c":["nanomedicine","society"],"k":"risk","x":"speculative","h":"indefinite","w":1551,"e":"Nothing to observe in people: no molecular assembler or self-replicating nanomachine has been built, and the nearest documented harm from engineered nanomaterials is fibre toxicity reported in mice.","n":10},{"s":"gut-microbiome","t":"Gut microbiome","d":"The community of bacteria, archaea, fungi and viruses living in the human intestine, and a much-claimed but weakly demonstrated lever on aging.","g":["aging","microbiome","gut","inflammation","fecal transplant","dysbiosis","mechanisms"],"b":"The gut microbiome is the community of bacteria, archaea, fungi and viruses that live in the human intestine, together with their genes, and the metabolites they produce from what the host eats. Most of it sits in the colon. It has become one of the most heavily invoked mechanisms in the biology of aging, implicated in chronic inflammation, frailty, drug response and cognition. It is also the mechanism with the widest gap between what has been shown in animals and what has been shown in people. What the community does Gut bacteria ferment dietary fibre that human enzymes cannot digest, releasing short-chain fatty acids that colonocytes use as fuel. They transform bile acids, synthesise vitamins, exclude incoming pathogens by occupying niches those pathogens need, and train the developing immune system. Germ-free animals, raised in isolators and never colonised, grow abnormal gut architecture and underdeveloped lymphoid tissue. That is the cleanest demonstration that the community shapes its host instead of merely living in it. The composition varies enormously between healthy people. Two adults with no illness can share only a modest fraction of their bacterial species while carrying similar metabolic capacities, which is why the field increasingly reports function rather than taxonomy. That variability is also the practical obstacle to defining what a \"healthy\" microbiome woul","c":["longevity","foundations"],"k":"concept","x":"emerging","h":"present","w":1539,"e":"Microbiome composition tracks health and survival in large human cohorts, and faecal transplant is approved only for recurrent C. difficile; every report of young microbiota extending life is in killifish or mice.","n":1},{"s":"hallmarks-of-aging","t":"Hallmarks of aging","d":"The consensus taxonomy of cellular and molecular processes held to drive mammalian aging, set out as nine mechanisms in 2013 and expanded to twelve in 2023.","g":["aging","biogerontology","mechanisms","damage","geroscience"],"b":"Hallmarks of aging are the cellular and molecular processes that, in the dominant framework of contemporary biogerontology, jointly account for the progressive functional decline of mammals over time. The list was set out as nine hallmarks in a 2013 review in Cell and expanded to twelve by the same five authors in 2023. Each candidate is supposed to satisfy three tests: it manifests during normal aging, experimentally worsening it accelerates aging, and experimentally easing it slows aging and extends healthy life. Overview Human mortality rises close to exponentially with adult age; the annual probability of death roughly doubles every eight years, a regularity described by Benjamin Gompertz in 1825. Beneath that curve sit thousands of measurable changes: shorter telomeres, stiffer arteries, fewer functional stem cells, higher circulating interleukin-6, drifting DNA methylation. The hallmarks framework reduces that inventory to a set of processes that are general across tissues, conserved across mammals, and at least arguably open to intervention. The framework gives a common vocabulary to a field that had spent decades arguing between rival single-cause theories. It also gives the field a target list. Most academic programmes and companies in the geroscience sector map their work onto one or more hallmarks, and reviewers treat hallmark membership as prima facie evidence that ","c":["longevity","foundations"],"k":"concept","x":"established","h":"present","w":1654,"e":"No hallmark has been shown to satisfy the framework's third criterion in humans; the amelioration results come from worms, flies and mice, and the human data are observational and correlational.","n":73},{"s":"he-jiankui-affair","t":"He Jiankui affair","d":"The 2018 announcement that twin girls had been born from CRISPR-edited embryos in Shenzhen, and the scientific condemnation and criminal prosecution that followed.","g":["crispr","embryos","heritable editing","bioethics","governance","china"],"b":"The He Jiankui affair was the first and so far only case in which human embryos edited with CRISPR were transferred to a womb and carried to term. On 25 November 2018 the Shenzhen-based biophysicist He Jiankui announced through online videos and an exclusive news interview that twin girls, given the pseudonyms Lulu and Nana, had been born from embryos in which he had disrupted the CCR5 gene, intending to make them resistant to HIV. The reaction from the international scientific community was immediate and close to unanimous condemnation, and He was convicted of illegal medical practice thirteen months later. Background He trained in physics in China, took a doctorate at Rice University, and did postdoctoral work at Stanford in single-molecule sequencing before returning to China in 2012 as an associate professor at the Southern University of Science and Technology in Shenzhen. He founded sequencing companies and was, by 2017, working privately on embryo editing while formally on unpaid leave from the university. The scientific setting mattered. Crispr cas9 had made embryo editing technically accessible; Chinese groups had published the first reports of editing non-viable human embryos in 2015, finding low efficiency and pervasive mosaicism. An international summit in Washington that December had declared clinical germline use irresponsible until safety questions were resolved a","c":["genetics","society"],"k":"event","x":"historical","h":"historical","w":1398,"n":21},{"s":"head-transplant","t":"Head transplantation","d":"The proposed transfer of a living human head onto a donor body, blocked chiefly by the inability to reconnect a severed spinal cord and rejected by mainstream neurosurgery.","g":["transplantation","spinal cord","neurosurgery","medical ethics","identity","fringe science"],"b":"Head transplantation is the proposed surgical transfer of a living head onto a body from a different individual, so that the recipient's brain is supplied by a new circulatory and musculoskeletal system. The procedure is more accurately called a body transplant, since the person who would survive is the one attached to the head. No human attempt has been made. What makes it implausible is the spinal cord rather than surgical technique: a completely severed cord cannot be repaired, and every proposal for performing the operation depends on solving that problem first. Animal precedents The experiments usually cited are older than the current debate and more limited than their reputation suggests. In the 1950s Vladimir Demikhov, a Soviet surgeon who did foundational work on cardiac and pulmonary transplantation, created dogs bearing a second head and forelimbs grafted onto the neck of an adult host. The grafted heads were conscious and could lap fluid. The animals survived days, dying of rejection. Robert White, a neurosurgeon at Case Western Reserve University, performed the most technically advanced version in 1970, transferring the head of one rhesus monkey onto the body of another with vascular anastomosis and hypothermic protection. The transplanted head regained consciousness, tracked with its eyes, and responded to stimuli; the animals survived for periods reported as hours","c":["bodies"],"k":"concept","x":"contested","h":"indefinite","w":1627,"e":"No human attempt has been made; living-subject work stops at Demikhov's 1950s dogs and White's 1970 rhesus monkeys, whose cords were never joined, and the 2017 human procedure was a rehearsal on two cadavers.","n":3},{"s":"healthspan","t":"Healthspan","d":"The portion of life spent in good health and function, as distinct from total lifespan; widely used as a goal but not standardized as a measure.","g":["aging","healthspan","frailty","public health","endpoints","demography"],"b":"Healthspan is the period of a person's life spent free of significant chronic disease and functional impairment. It is the quantity most longevity research says it is trying to extend, and the one it measures least consistently. Unlike lifespan, which has a single unambiguous endpoint, healthspan requires a decision about what counts as ill health, and that decision changes the answer by years. Why the definition matters Lifespan is settled by a death certificate. Healthspan requires drawing a line somewhere on a continuum of decline, and the plausible lines are far apart. A definition based on the first diagnosis of any chronic condition puts the end of healthspan in the fifties for most people in high-income countries, since hypertension and osteoarthritis are near-universal. A definition based on loss of independence puts it in the late seventies or eighties. A definition based on self-rated health tracks neither reliably. The choice has practical consequences. It determines whether a given intervention appears to extend healthspan, compress it, or leave it unchanged, and it makes results from different studies non-comparable. The same cohort can show a decade of difference depending on which operationalization the analyst chose. Terminology \"Healthspan\" has no agreed technical definition and no standard measurement instrument. Papers using the word should be read for how th","c":["longevity","foundations"],"k":"concept","x":"established","h":"present","w":1138,"n":57},{"s":"heat-and-cold-exposure","t":"Heat and cold exposure","d":"Deliberate exposure to heat or cold, from sauna bathing to cold-water immersion, as a health practice built on a hormetic mechanism whose effect on human lifespan is unmeasured.","g":["sauna","cold exposure","hormesis","brown adipose tissue","heat shock proteins","recovery","observational epidemiology"],"b":"Heat and cold exposure is the deliberate use of thermal stress, in forms such as sauna bathing, hot-water immersion, cold plunging and winter swimming, as a general health practice rather than as treatment for a named disease. The case for it rests on hormesis: a stressor too mild to injure provokes a defensive response that leaves the organism better off than it was. The cellular mechanisms invoked are real and well characterized, but the human outcome evidence is much thinner than the public conversation implies, and the strongest piece of it is a cohort study that cannot establish cause. How it works Hormesis names a dose-response curve in which a small amount of a stressor produces the opposite effect to a large amount, and heat and cold are among its textbook cases. A rise in core temperature triggers the heat-shock response: chaperone proteins are transcribed rapidly and set about refolding or disposing of damaged protein, a direct intervention in the protein quality-control system that fails with age and appears in most catalogues of the Hallmarks of aging. In nematodes, the heat-shock transcription factor HSF-1 is required for the long life of the insulin-signalling mutants that Cynthia Kenyon's laboratory made famous, and raising its activity extends life in the same species. Heat also imposes a circulatory load. Skin blood flow rises sharply, heart rate climbs, plasma","c":["longevity","enhancement"],"k":"intervention","x":"contested","h":"present","w":1560,"e":"Randomized trials show short-term changes in blood pressure, vascular function and mood; the mortality findings come from an observational Finnish cohort of men, and no trial has tested lifespan or healthspan.","a":"Unregulated and widely available: public and gym saunas, home units, cold-plunge studios and open water, at costs from a swim ticket to four-figure equipment.","r":"reversible","n":11},{"s":"human-cloning","t":"Human cloning","d":"Producing a human genetically identical to an existing person by somatic cell nuclear transfer, demonstrated to the blastocyst stage and never taken to a pregnancy.","g":["cloning","reproduction","stem cells","bioethics","regulation","identity"],"b":"Human cloning is the production of a person genetically identical to an existing individual, almost always understood to mean somatic cell nuclear transfer into an egg. Nuclear transfer has produced live offspring in more than twenty mammalian species, including primates, and has produced human embryos and stem cell lines. No human pregnancy from it has been reported anywhere. Law and technique explain part of that; a collapse in motivation explains as much. Two things called cloning Reproductive cloning aims at a live birth. Therapeutic cloning, more precisely called nuclear transfer for stem cell derivation, aims only at a blastocyst from which embryonic stem cells genetically matched to a patient can be taken. The two share every step up to embryo transfer and part completely after it. Between about 1998 and 2007 the distinction mattered enormously, because patient-matched stem cells were the main scientific argument for permitting nuclear transfer at all. It stopped mattering when Induced pluripotent stem cells arrived. Reprogramming a skin cell with the Yamanaka factors produces patient-matched pluripotent cells without an egg, without an embryo, and without the ethical objection that dominated a decade of legislation. Within a few years of being legalised in the places that legalised it, therapeutic cloning was largely obsolete. How nuclear transfer works An unfertilised ","c":["reproduction","genetics"],"k":"technology","x":"contested","h":"indefinite","w":1215,"e":"Nuclear transfer has produced human blastocysts and embryonic stem cell lines in culture; no human pregnancy or birth from a cloned embryo has been documented, and all live-birth data are from other mammals.","a":"Not obtainable: reproductive cloning is prohibited by statute in most countries with a biotechnology sector and no clinic offers it, while nuclear transfer for research is done in a handful of laboratories.","r":"irreversible","n":13},{"s":"human-digital-twins","t":"Human digital twins","d":"Computational models of an individual person's physiology, built from that person's own data and run to predict what an intervention would do before it is attempted.","g":["simulation","in silico trials","personalized medicine","computational modelling","medical devices","cardiology"],"b":"Human digital twins are computational models of an individual person's physiology, built from that person's own imaging, measurements and sensor data and run to predict what an intervention would do before it is attempted. The idea comes from aerospace and manufacturing, where a simulation of one specific engine is kept synchronised with the engine itself and used to decide when to service it. Medicine has no whole-body equivalent and is not near one. What exists is a set of organ- and device-specific models, each narrow, and each personalised in a few respects and generic in the rest. What the term covers Three different objects travel under the name, and most of the subject lies in telling them apart. The first is a mechanistic simulation whose geometry is taken from a patient's scan and whose equations come from physics and physiology: blood flow through that person's coronary tree, electrical propagation around the scar in that person's ventricle, the field a stimulation lead produces in that person's brain. The second is a statistical or machine-learned predictor fitted to population data and evaluated on one person's record, closer in kind to a biological-age estimate than to a simulation. The third is a longitudinal data display, in which a record assembled from Wearable health sensors, Continuous glucose monitoring and the laboratory is rendered next to a picture of a b","c":["bodies","foundations"],"k":"technology","x":"experimental","h":"2040s","w":2135,"e":"In patients, simulation is routine only for radiotherapy dose and CT-derived coronary physiology; virtual-heart ablation planning rests on small studies. No whole-body twin exists for any person.","a":"Organ-specific models are sold as regulated software and reimbursed in some health systems, notably CT-derived coronary flow analysis. Products marketed as whole-person twins are usually dashboards.","r":"reversible","n":12},{"s":"human-enhancement","t":"Human enhancement","d":"The deliberate use of biomedical or technical means to extend human capacities beyond what is needed to restore or maintain ordinary health.","g":["enhancement","bioethics","therapy","cognition","fairness","autonomy","regulation"],"b":"Human enhancement is the deliberate use of biomedical, pharmacological or technical means to raise a human capacity above the level required for ordinary health, rather than to restore a capacity lost to disease or injury. The category is defined by contrast: an intervention counts as enhancement when it is not therapy. That contrast is hard to draw cleanly, so most of the philosophical work on the subject concerns the boundary itself rather than any particular technique. The therapy-enhancement boundary The standard way of drawing the line appeals to species-typical functioning. On Christopher Boorse's biostatistical account, health is the statistically normal contribution of each organ and process to survival and reproduction for an organism of a given age and sex; disease is subnormal functioning, and medicine's job is to restore the norm. Norman Daniels built a theory of just health care on a similar footing: society owes its members treatment that protects the normal opportunity range, and enhancement beyond it is a private matter. The account explains some things well. It shows why insurers pay for insulin and not for a cosmetic procedure, and why growth hormone for a child with a pituitary tumour is treated differently from growth hormone for a healthy short child. It also fails in predictable places. Vaccination raises immune competence above the untreated norm and is u","c":["enhancement","foundations"],"k":"concept","x":"contested","h":"present","w":1727,"n":47},{"s":"germline-editing","t":"Human germline editing","d":"Modification of human embryos, eggs, or sperm so that the genetic change is inherited by the resulting child and by all of their descendants.","g":["crispr","embryos","heritable editing","bioethics","governance","reproduction"],"b":"Human germline editing is the deliberate alteration of DNA in gametes, zygotes, or early embryos such that the change is carried by every cell of the resulting person and passed to their children. It is the practice that separates genetic medicine from genetic inheritance. Almost every scientific body that has examined it has concluded that clinical use is not currently justified, and it has been attempted in a clinic exactly once, in 2018, by a researcher subsequently imprisoned in China. Definition and scope The germ line is the cell lineage that produces eggs and sperm. Edits made anywhere else (in liver, muscle, blood, retina) die with the patient, which is why Somatic gene therapy is regulated as ordinary medicine and heritable editing is not regulated as medicine at all in most countries but prohibited outright. The boundary is less crisp than the vocabulary suggests. Editing spermatogonial stem cells in an adult man is technically somatic but heritable in effect. Mitochondrial replacement therapy, legal in the United Kingdom since 2015 and used there in births reported in 2025, alters the mitochondrial genome transmitted down the maternal line; it is heritable, yet it was legislated as an exception rather than treated as germline modification, on the argument that it swaps an organelle rather than editing nuclear DNA. Whether that distinction is principled or convenient ","c":["genetics","society","reproduction"],"k":"technology","x":"contested","h":"2040s","w":1957,"e":"One unsanctioned clinic case produced children from CCR5-edited embryos in 2018 and 2019; all other human work is in research embryos cultured for days, where editing is frequently mosaic and can delete or lose the target chromosome.","a":"Obtainable through no lawful route: transfer of an edited embryo to a womb is forbidden wherever the question is regulated, and research use is confined to licensed embryo work.","r":"irreversible","n":44},{"s":"human-hibernation","t":"Human hibernation and torpor","d":"The proposal to induce a hibernation-like state of suppressed metabolism in people, and the distance between rodent torpor circuits and any clinical human application.","g":["torpor","hypothermia","metabolism","spaceflight","neuroscience","suspended animation"],"b":"Human hibernation and torpor is the proposal to place people in a state of deliberately suppressed metabolic rate and lowered body temperature, either for medical stabilisation or to reduce the physiological and logistical costs of long spaceflights. No human has ever been put into torpor. The clinical practices that resemble it, such as cooling after cardiac arrest and deep hypothermic circulatory arrest during aortic surgery, lower temperature from the outside and accept the metabolic consequences. A hibernating animal works the other way round. What torpor is Torpor is a regulated reduction in metabolic rate and body temperature, entered and exited under the animal's own control. Hibernation is a seasonal pattern of multi-day torpor bouts separated by brief, energetically expensive arousals back to normal temperature. Daily torpor, seen in some rodents and hummingbirds, is the same mechanism on a shorter cycle. The key word is regulated. In deep torpor, an arctic ground squirrel's core temperature can fall below the freezing point of water and its metabolic rate to a few per cent of basal, with heart rate in the single digits, and it rewarms itself on schedule without external assistance. Metabolic suppression precedes cooling rather than following from it. The animal turns down its own oxygen consumption first, and the temperature drop follows. Bears make the point differen","c":["space","bodies"],"k":"concept","x":"experimental","h":"2040s","w":1748,"e":"No human has been placed in torpor; every induced-torpor result is from mice and rats, and all human cooling to date is hypothermia imposed from outside against a defended set point.","n":12},{"s":"human-ai-merger","t":"Human–AI merger","d":"The proposal that humans and artificial intelligence will form a single cognitive system rather than remaining separate agents that merely use one another.","g":["artificial intelligence","brain-computer interface","bandwidth","identity","cognition","extended mind"],"b":"Human-AI merger is the claim that people and artificial intelligence will become coupled so closely that the combined system, rather than a user and a tool, is the relevant unit of cognition and, on stronger versions, of identity. The idea is invoked most often as the stated rationale for high-bandwidth brain-computer interfaces, and as a proposed alternative to being economically or intellectually displaced by autonomous Artificial general intelligence. It is a family of quite different theses, and they are rarely distinguished. The two theses The centaur thesis holds that human-machine teams outperform either party alone, and that the future of capability lies in division of labour rather than replacement. It makes claims that can be tested today. The merger thesis is stronger. It holds that direct neural interfaces, continuous prediction of intent, or the gradual delegation of cognitive functions will make the coupling tight enough that drawing a boundary between the person and the system stops being meaningful. This is the version that carries implications for Personal identity and continuity, and it has no demonstrated instance at any scale. Intellectual history J. C. R. Licklider set out the framing in 1960, arguing that in the near term computers and humans would occupy complementary roles, with humans setting goals and formulating hypotheses while machines handled routi","c":["foundations","cybernetics","minds"],"k":"concept","x":"speculative","h":"2040s","w":1504,"e":"No merged system exists at any scale; the strongest human results are intracortical implants in small numbers of people with paralysis, decoding attempted speech or handwriting at tens of words per minute.","n":16},{"s":"humanity-plus","t":"Humanity+","d":"The main international transhumanist membership organization, founded in 1998 as the World Transhumanist Association and now a small education and advocacy body.","g":["transhumanism","movements","advocacy","bioethics","nonprofit","intellectual history"],"b":"Humanity+ is an international nonprofit membership organization founded in 1998 as the World Transhumanist Association to advocate for the ethical use of technology to extend human capacities. It was created as a deliberately academic and politically non-aligned alternative to Extropianism, and for roughly a decade it was the institutional centre of Transhumanism. Its influence has since dispersed into specialized fields such as AI safety, longevity biotech and bioethics, and the organization itself now operates at a much smaller scale, as an education and advocacy body. Overview The WTA was founded to make transhumanism defensible in an academic seminar. The extropians had a libertarian politics, a self-consciously informal style and no peer-reviewed output. The new body offered a journal, a declaration written in the register of a human-rights document, and a leadership drawn from philosophy departments, and it presented transhumanism as a normative position about technology and human welfare rather than as a subculture. The repositioning succeeded for the ideas more than for the institution. The arguments the WTA promoted are now standard reference points in bioethics syllabi, while the organization that promoted them has few staff and little visible programme. History Nick bostrom, then a philosophy doctoral student, and David Pearce, author of the online manifesto The Hedo","c":["organizations","people"],"k":"organization","x":"established","h":"present","w":1222,"n":5},{"s":"immunosenescence","t":"Immunosenescence","d":"The age-related remodelling of the immune system, in which responses to unfamiliar antigens weaken while chronic activation against familiar ones persists.","g":["aging","immunity","thymus","t cells","vaccines","mechanisms","cytomegalovirus"],"b":"Immunosenescence is the set of changes that accumulate in the immune system with age: a shrinking capacity to respond to antigens the body has not met before, alongside persistent low-grade activation against antigens it has. It is the immune component of biological aging and accounts for a substantial part of the rise in mortality with age. Infection kills disproportionately in the old, latent viruses reactivate, and immune control of transformed cells, one of the body's defences against Cancer, weakens. What changes The thymus, where T cells are selected and licensed, begins involuting in childhood and is largely replaced by fat by middle age. No other organ loses so much of itself so early with so little clinical notice. As it shrinks, the supply of new naive T cells falls steeply, and the existing pool has to be maintained by division rather than replacement. The composition of the T-cell pool shifts as a result. Naive T cells decline, memory and terminally differentiated effector cells expand, and the diversity of the T-cell receptor repertoire contracts. Deep sequencing of receptor repertoires in donors from childhood to old age found diversity tracking the naive T-cell fraction, which fell roughly linearly to about the age of 70. A narrower repertoire can recognise a narrower set of antigens, and that is the mechanistic link between an aged immune system and poor defence","c":["longevity","bodies"],"k":"concept","x":"established","h":"present","w":1368,"e":"Thymic involution, naive T-cell decline, repertoire contraction and weaker vaccine responses are all measured directly in people; every proposal to reverse them has been tested only in mice or in small uncontrolled human studies.","n":6},{"s":"in-vitro-fertilisation","t":"In vitro fertilisation","d":"The routine clinical procedure in which eggs are fertilised outside the body and an embryo is transferred to a uterus, and the platform every other embryo technology is built on.","g":["reproduction","ivf","embryo selection","fertility","regulation","bioethics"],"b":"In vitro fertilisation is the procedure in which eggs are recovered from ovaries, combined with sperm in a laboratory dish, cultured for a few days, and transferred to a uterus as an embryo. It is the oldest and most widely performed of the assisted reproductive technologies, and its reach extends far beyond infertility medicine. Almost every technique this wiki covers under reproduction, from Embryo selection to Germline editing, is an operation on an embryo that exists only because of IVF. How a cycle works A cycle runs in four steps: stimulation, egg collection, fertilisation and culture, transfer. Injected gonadotrophins stimulate the ovaries to mature many follicles at once, where a natural cycle matures one. Ultrasound and blood hormone measurements track the response, and eggs are collected under sedation by a needle passed through the vaginal wall. In the laboratory the eggs are either mixed with prepared sperm or, where sperm quality is poor, injected with one sperm each by intracytoplasmic sperm injection (ICSI). Fertilised eggs are cultured for two to six days, usually to the blastocyst stage. One embryo is transferred; the rest are vitrified and stored. Two changes have reshaped that sequence since the 1990s. ICSI, first reported by a Brussels group in 1992, made severe male-factor infertility treatable and is now used in a majority of cycles worldwide, including ma","c":["reproduction","society"],"k":"technology","x":"established","h":"present","w":1276,"e":"Between ten and thirteen million children had been born after assisted reproduction by 2018 and several million since; live-birth rates fall steeply with the age of the egg, and birth defects are modestly more common than after natural conception.","a":"Available in most countries with a fertility sector but funded unevenly: NHS-funded cycles fell from 35 percent of UK treatments in 2019 to 27 percent in 2023, and a self-funded cycle costs several thousand pounds or dollars before optional extras.","r":"irreversible","n":1},{"s":"in-vitro-gametogenesis","t":"In vitro gametogenesis","d":"Making functional eggs or sperm from pluripotent stem cells in culture, achieved end to end in mice and still short of the meiotic stages in humans.","g":["reproduction","stem cells","gametes","fertility","embryo selection","bioethics"],"b":"In vitro gametogenesis is the production of functional eggs or sperm from pluripotent stem cells in culture, without a gonad. In mice the full female cycle has been closed: embryonic stem cells have been converted to oocytes entirely in a dish, fertilised, and carried to healthy pups whose own cells could start the cycle again. In humans, the same protocols stall well before meiosis. The field is defined by the gap between the mouse and human results, and that gap has not narrowed as quickly as the mouse work led people to expect. How it works Germ cells are set aside early in development and then follow a schedule no other lineage repeats. They erase most of their DNA methylation, re-establish sex-specific imprints, and halve their chromosome number through meiosis. In the female line they also grow enormously while stockpiling the maternal factors an embryo needs before its own genome switches on. Reconstituting that in culture means reproducing each stage in order, and the standard route has four steps. 1. Pluripotency. Start from embryonic stem cells or from Induced pluripotent stem cells made by reprogramming a somatic cell such as a skin fibroblast or a blood cell. 2. Germline specification. Push the cells through an epiblast-like intermediate and then, with BMP signalling and the right transcription factors, into primordial germ cell-like cells. In humans, SOX17 rather t","c":["reproduction","genetics"],"k":"technology","x":"experimental","h":"2030s","w":1749,"e":"Human pluripotent cells have been carried as far as oogonia in culture and stop before meiosis; no human egg or sperm has been made in vitro, and the complete cycle exists only in mice.","a":"Not available anywhere: no jurisdiction permits clinical use, the UK statute excludes such gametes by construction, and the work is confined to research laboratories and a few companies.","r":"irreversible","n":21},{"s":"in-vivo-car-t","t":"In vivo CAR-T therapy","d":"A way of making chimeric antigen receptor T cells inside the patient's body, by infusing a targeted viral vector or lipid nanoparticle instead of manufacturing cells in a facility.","g":["cell therapy","cancer","gene therapy","immunotherapy","oncology","delivery","clinical trials"],"b":"In vivo CAR-T therapy puts the chimeric antigen receptor gene into a patient's own T cells while those cells are still inside the patient, using an infused vector that seeks out T cells rather than a factory that grows them. Seven conventional CAR-T products, all directed at CD19 or BCMA, are approved in the United States and Europe; each one collects a person's lymphocytes, transduces them in a facility over several weeks, and reinfuses them after lymphodepleting chemotherapy, at a cost exceeding hundreds of thousands of dollars per patient. The in vivo version replaces that chain with a single intravenous dose. As of November 2026 nine patients with multiple myeloma have been described in peer-reviewed phase 1 reports, alongside five lupus patients in a shorter peer-reviewed letter, and nothing is approved. How it works The older route to making CAR-T therapy cheaper runs through donors rather than through delivery. Allogeneic, off-the-shelf products start from a healthy donor's cells and knock out TRAC and B2M with CRISPR-Cas9 or TALENs to prevent graft-versus-host disease and rejection; they still require ex vivo engineering, heavy lymphodepletion, and have shown limited persistence in patients. In vivo delivery attacks the problem from the other end, leaving the cells where they are. Two delivery platforms are in clinical development, and they differ in almost every respec","c":["genetics","nanomedicine"],"k":"technology","x":"experimental","h":"2030s","w":2309,"e":"Two peer-reviewed phase 1 cohorts totalling nine patients with multiple myeloma report responses without lymphodepletion, alongside cytokine release syndrome, four deaths, and a median progression-free survival of 4.0 months in the four followed longest.","a":"Nothing is approved anywhere; the only route is more than fifteen registered first-in-human phase 1 trials in China, Australia, the United States and Europe, and no price has been set.","r":"context","n":3},{"s":"induced-pluripotent-stem-cells","t":"Induced pluripotent stem cells","d":"Adult cells reprogrammed back to an embryonic-like state, capable of becoming any cell type in the body and of being derived from a specific patient.","g":["stem cells","reprogramming","regenerative medicine","cell therapy","disease modelling"],"b":"Induced pluripotent stem cells are ordinary adult cells that have been reprogrammed into an embryonic-like state from which they can be differentiated into any cell type in the body. Because they are made from a patient's own tissue, they sidestep both the embryo destruction that constrains embryonic stem cell work and, in principle, the immune rejection that constrains transplantation. They have transformed laboratory biology within a decade and have so far produced no approved therapy. Derivation An iPSC line begins with an accessible somatic cell: a skin fibroblast, a peripheral blood mononuclear cell, or a renal epithelial cell shed into urine. The Yamanaka factors are introduced, and over two to four weeks a small fraction of the treated cells activate the endogenous pluripotency network and form colonies that can be picked, expanded and banked. Vector choice decides whether a line can ever reach a patient, so clinical derivation uses footprint-free methods: Sendai virus, episomal plasmids or synthetic mRNA, none of which leave a permanent trace in the genome. The effort then shifts from making the line to qualifying it, through karyotyping, copy-number analysis, sequencing for acquired mutations, and confirmation that no undifferentiated cells survive into the final product. Qualification rather than derivation is what makes a clinical-grade line expensive, and that cost ","c":["bodies","genetics"],"k":"technology","x":"emerging","h":"late 2020s","w":1176,"e":"Small early-phase trials in people report that iPSC-derived retinal, corneal, dopaminergic and islet grafts survive and in some cases function; none is randomized and no product has marketing approval as of mid-2026.","a":"Research lines are widely banked and sold for laboratory use; as a therapy there is nothing to obtain outside small early-phase trials, since no iPSC-derived product is approved anywhere.","r":"difficult","n":35},{"s":"inflammaging","t":"Inflammaging","d":"The chronic, low-grade, sterile inflammation that develops with age in the absence of infection, and its disputed role in frailty and age-related disease.","g":["aging","inflammation","immunology","senescence","biomarkers","mechanisms"],"b":"Inflammaging is the chronic, low-grade, systemic inflammation that develops with age without an identifiable infection. It is measured by modestly elevated circulating interleukin-6, C-reactive protein and tumour necrosis factor, levels far below those of acute illness but persistently above those of young adults. Claudio Franceschi introduced the term in 2000 as part of an evolutionary argument: the immune responses that protect against pathogens in early life become maladaptive when sustained across decades. Chronic inflammation was added as a distinct entry to the Hallmarks of aging in 2023. The observation Inflammatory markers rise with age in essentially every population studied, and their level predicts outcomes. Interleukin-6 concentration in older adults is associated with subsequent disability, frailty, cognitive decline and all-cause mortality, consistently enough that it is sometimes described as the single most informative blood measure in geriatric epidemiology. Elevated C-reactive protein carries similar predictive weight for cardiovascular events. The elevation is small in absolute terms. It is chronic, not episodic; sterile, in that no pathogen is present; and heterogeneous, in that individuals of the same age differ widely. Some very old people show inflammatory profiles resembling those of middle-aged adults, and centenarian cohorts have been reported to combi","c":["longevity"],"k":"concept","x":"established","h":"present","w":1107,"e":"Inflammatory markers rise with age in essentially every human population studied and predict mortality and frailty; the causal human evidence comes from cardiovascular trials of specific anti-inflammatory drugs, not from aging endpoints.","n":40},{"s":"intelligence-amplification","t":"Intelligence amplification","d":"The project of raising human problem-solving capacity by improving the tools, notations and organisations that thinking runs on rather than by altering the brain.","g":["cognition","enhancement","tools","collective intelligence","human-computer interaction","ai"],"b":"Intelligence amplification is the strategy of increasing what people can figure out by improving the systems they think with, such as notations, instruments, software and institutions, rather than by modifying the brain itself. Its proponents argue that essentially all historical gains in human cognitive capability have come this way, and that the biological routes covered elsewhere on this wiki are both harder and less effective by comparison. The idea is old enough to have a settled literature, and unsettled enough that nobody agrees on how to measure the result. Origins W. Ross Ashby used the phrase \"intelligence amplifier\" in the mid-1950s, arguing by analogy with power amplification that a machine could amplify a small amount of human selective judgement into a large amount of problem-solving, provided the human supplied the selection criterion. Vannevar Bush had already sketched the practical version a decade earlier in \"As We May Think\", proposing the memex, a desk-sized associative index that would let a researcher build and share trails through a personal library. J. C. R. Licklider gave the position its most-quoted formulation in \"Man-Computer Symbiosis\", predicting a period in which humans set goals and formulate hypotheses while machines do the routine work that prepares the way for insight, and observing that most of what he did as a researcher was clerical. Dougla","c":["enhancement","minds"],"k":"concept","x":"established","h":"present","w":1455,"n":12},{"s":"interventions-testing-program","t":"Interventions Testing Program","d":"A National Institute on Aging programme that tests whether candidate anti-aging compounds extend lifespan in genetically heterogeneous mice, run in parallel at three sites.","g":["aging","biogerontology","lifespan","mice","drug testing","replication"],"b":"The Interventions Testing Program (ITP) is a programme of the US National Institute on Aging that tests whether candidate compounds extend the lifespan of mice, running every test in parallel at three independent sites under an identical protocol. Since its first cohorts in 2004 it has become the closest thing biogerontology has to a benchmark. A lifespan claim that survives the ITP is taken seriously, and one that fails there is substantially weakened however striking the original report. Its most consequential outputs include the 2009 demonstration that Rapamycin extends mouse lifespan when begun late in life, and a long list of famous candidates that did nothing. Overview The ITP exists because the mouse-longevity literature it inherited was unreliable. A lifespan result from one laboratory, in one inbred strain, on one diet, frequently failed to reproduce anywhere else, and a compound could look life-extending simply because it corrected a quirk of a single genotype. The programme's design addresses each of these failure modes. Every compound is tested simultaneously at the Jackson Laboratory, the University of Michigan, and the University of Texas Health Science Center at San Antonio. The mice are genetically heterogeneous UM-HET3 animals, bred as a four-way cross so that every mouse is a genetically distinct sibling of every other, which prevents any result from being an ","c":["organizations","longevity"],"k":"organization","x":"established","h":"present","w":1390,"n":3},{"s":"isomorphic-labs","t":"Isomorphic Labs","d":"Alphabet's London-based AI drug-design company, founded in 2021 by Demis Hassabis to build on AlphaFold; it co-developed AlphaFold 3 and has no drug in human trials as of October 2026.","g":["drug discovery","machine learning","alphafold","structural biology","google","biotech"],"b":"Isomorphic Labs is an Alphabet-owned company in London that designs drug candidates with machine-learning models, founded in 2021 by Demis Hassabis to carry DeepMind's protein structure work into pharmaceutical research. It co-developed AlphaFold 3 with Google DeepMind, has research collaborations with Eli Lilly, Novartis and Johnson & Johnson, and has raised $2.7 billion in external funding rounds. As of October 2026 no molecule it designed has been given to a person, so the clinical value of its approach is still untested. It is one of the best-funded tests of whether structure prediction can be turned into medicines. Overview Isomorphic presents drug discovery as an engineering problem. Its models predict how a candidate molecule binds its target and what properties it will have, so that fewer compounds need to be made and tested in the laboratory. It is a vertically integrated form of Ai drug discovery: the company builds its own models, generates its own data and runs its own medicinal chemistry, and it says it will take candidates into clinical trials itself rather than only licensing them out. Its stated mission is to \"solve all disease\", an aspiration with no timeline attached. The company works on two tracks. Partnered programmes with large drug companies bring in money and targets chosen by the partner. Wholly owned internal programmes, which the company describes as ","c":["organizations","foundations"],"k":"organization","x":"emerging","h":"late 2020s","w":1564,"n":4},{"s":"jennifer-doudna","t":"Jennifer Doudna","d":"American biochemist who co-authored the 2012 paper showing CRISPR-Cas9 could be programmed to cut chosen DNA sequences, and shared the 2020 Nobel Prize in Chemistry.","g":["crispr","gene editing","rna","nobel prize","governance","biochemistry"],"b":"Jennifer Doudna is an American biochemist and structural biologist who, with Emmanuelle Charpentier, demonstrated in 2012 that the bacterial CRISPR-Cas9 system could be reduced to two components and directed to cut any chosen DNA sequence by a single engineered guide RNA. The result turned a bacterial immune mechanism into a general-purpose editing tool, and she shared the 2020 Nobel Prize in Chemistry for it. She has since become one of the field's most active voices on governance, particularly on the line between somatic and heritable editing. Career Doudna grew up in Hilo, Hawaii, took a degree in biochemistry at Pomona College, and completed a doctorate at Harvard in 1989 with Jack Szostak, working on self-replicating RNA. As a postdoctoral researcher with Thomas Cech in Colorado she solved the crystal structure of a large catalytic RNA domain, one of the first high-resolution views of RNA folding into a defined three-dimensional enzyme. Between them, the two projects treated RNA both as an information carrier and as a machine, a combination that set up everything that followed. She joined Yale in 1994 and moved to the University of California, Berkeley, in 2002. Her laboratory came to CRISPR through structural work on RNA-guided processes rather than through microbiology. Bacterial CRISPR arrays had been described since the late 1980s, and their role in adaptive immunity w","c":["people","genetics"],"k":"person","x":"established","h":"present","w":1053,"n":8},{"s":"julian-savulescu","t":"Julian Savulescu","d":"Australian bioethicist who formulated procreative beneficence and, with Ingmar Persson, the argument for moral bioenhancement; the leading academic advocate of human enhancement.","g":["bioethics","enhancement","embryo selection","moral enhancement","philosophy"],"b":"Julian Savulescu is an Australian bioethicist who holds that parents have a moral reason to select the children expected to have the best lives, that enhancement is continuous with medicine rather than opposed to it, and that humanity's moral capacities are now the binding constraint on its technological ones. Trained as a physician and as a philosopher under Peter Singer, he has been the most systematic academic defender of Human enhancement since the early 2000s, and the figure whose arguments bioconservative critics most often answer. Career Savulescu qualified in medicine at Monash University and completed a doctorate there in philosophy, working on rationality and end-of-life decision-making. He took the Uehiro Chair in Practical Ethics at Oxford in 2002 and founded and directed the Oxford Uehiro Centre for Practical Ethics, which became the main European base for analytic work on enhancement, neuroethics and research ethics. He edited the Journal of Medical Ethics for close to two decades. In August 2022 he moved his primary post to the National University of Singapore, where he is the Chen Su Lan Centennial Professor in Medical Ethics and directs its Centre for Biomedical Ethics. He retains Oxford and Melbourne affiliations, including a biomedical ethics group at the Murdoch Children's Research Institute. His output is unusually broad for the field. It covers embryo sele","c":["people","society"],"k":"person","x":"established","h":"present","w":1046,"n":9},{"s":"kernel","t":"Kernel (neurotechnology company)","d":"American neurotechnology company founded by Bryan Johnson in 2016 that builds non-invasive headsets measuring brain haemodynamics for research and brain-health scans.","g":["neurotechnology","fnirs","brain imaging","bryan johnson","brain age","wearables"],"b":"Kernel is an American neurotechnology company, founded in 2016 by the payments entrepreneur Bryan johnson, that builds non-invasive headsets for measuring brain activity. It began as a plan for an implanted Memory prosthesis and dropped that goal within about six months. Since 2020 its main product has been Kernel Flow, a helmet that uses time-domain functional near-infrared spectroscopy (TD-fNIRS) to track blood-oxygen changes in the outer cortex. As of October 2026 Kernel sells Flow to researchers and offers \"brain age\" scans through a few longevity clinics; no Kernel product is cleared by the US Food and Drug Administration to diagnose or treat disease. Overview Kernel is often grouped with Neuralink and Synchron as a Brain computer interface company, and Johnson calls Flow a \"brain interface\". The label hides a basic difference: Kernel's current devices are worn, not implanted, and only record. They do not stimulate the brain, drive a cursor or decode the content of thought. Flow measures changes in oxygenated and deoxygenated haemoglobin, a signal that lags neural activity by seconds and comes only from the outer few centimetres of cortex. The stated aim is to make brain function as routinely measurable as heart rate or blood chemistry. A 2025 company newsletter says the team held itself to \"no gimmicks, no toys, no sci-fi fantasies\", a long way from the 2016 launch, when ","c":["organizations","cybernetics"],"k":"organization","x":"emerging","h":"late 2020s","w":1625,"n":2},{"s":"klotho","t":"Klotho","d":"A gene and hormone whose loss shortens mouse lifespan and whose best-demonstrated job is phosphate control, proposed as a longevity factor on largely non-human evidence.","g":["aging","longevity","kidney","fgf23","cognition","mouse studies","hormones"],"b":"Klotho is a gene, and the protein it encodes, whose loss in mice produces a syndrome of early-onset frailty and whose overexpression lengthens mouse lifespan. Its best-demonstrated role is a routine physiological one: α-klotho is the co-receptor that lets the bone hormone FGF23 act on the kidney and regulate phosphate. The longevity reading of klotho rests on mouse genetics, human association studies that replicate unevenly, and one memory experiment in aged rhesus monkeys. No study has yet reported what klotho does when given to a person. Overview The KL gene encodes α-klotho, a single-pass transmembrane protein expressed most heavily in the kidney tubule, the parathyroid gland and the choroid plexus. Its large extracellular domain is cleaved by cell-surface proteases and released into blood, urine and cerebrospinal fluid, so the same gene yields a local receptor component and a circulating hormone. A paralogue, β-klotho, performs the equivalent co-receptor role for the metabolic hormones FGF21 and FGF19. The klotho proteins are therefore shared components of an endocrine system, not a single anti-aging switch. The distinction matters for how the subject is discussed. Most of the interest in klotho concerns the shed, soluble form and its supposed systemic effects, while most of the mechanism actually worked out concerns the membrane form and mineral metabolism. Reviews and pre","c":["longevity","genetics"],"k":"concept","x":"experimental","h":"2030s","w":1583,"e":"In people the evidence is observational: KL-VS genotype and serum klotho track cognition and mortality inconsistently across cohorts, and no trial of administered klotho has reported results.","a":"Not available as a therapy; two phase 1 studies of klotho gene and mRNA delivery were registered by 2026, one of them dosing volunteers outside United States regulatory jurisdiction.","n":2},{"s":"lab-grown-organs","t":"Lab-grown organs","d":"The attempt to produce whole transplantable organs from cells rather than donors, currently limited to simple tissues, islet clusters and organs grown inside host animals.","g":["regenerative medicine","transplantation","stem cells","chimeras","immunology","organ shortage"],"b":"Lab-grown organs are transplantable organs produced from cells rather than taken from a donor. The category is defined by ambition rather than method: it includes organs built on a scaffold, organs grown inside a host animal, and organs regenerated in place inside the patient. As of 2026 no solid vascularized organ made by any of these routes has been transplanted into a human. What has reached patients is a narrower set of engineered tissues, and understanding why the boundary falls where it does is more useful than any timeline. What counts The functional distinction is between organs that are essentially sheets or clusters and organs that are perfused three-dimensional structures with an arterial inlet and a venous outlet. The first category has clinical products. Cultured epidermal grafts, engineered skin, cultured limbal epithelium for corneal repair, and allogeneic cultured thymus tissue for children born without a thymus are all approved somewhere. Stem-cell-derived pancreatic islet clusters, which are Organoids in construction if not in name, have produced insulin independence in most participants of small type 1 diabetes trials, using standard immunosuppression. This is arguably the first case of a lab-grown endocrine organ doing an organ's job in a person, even though it is delivered as a suspension of cell clusters into the portal vein rather than as an anatomical pa","c":["bodies"],"k":"technology","x":"experimental","h":"2040s","w":1506,"e":"Engineered skin, corneal and thymus tissue are approved and implanted in patients, and small trials of stem-cell-derived islets have produced insulin independence; no solid vascularized organ has been transplanted into a person.","a":"Only the simple tissues can be obtained: skin, limbal and thymus products are approved in some countries, stem-cell-derived islets are trial-only, and no solid organ is purchasable at any price.","r":"difficult","n":17},{"s":"leon-kass","t":"Leon Kass","d":"American physician and bioethicist who chaired the President's Council on Bioethics and made the strongest philosophical case that mortality gives human life its meaning.","g":["bioethics","bioconservatism","human dignity","cloning","mortality"],"b":"Leon Kass is an American physician, biochemist and bioethicist. He argues that the central danger of biotechnology is the erosion of the goods that make a human life worth living, rather than accident or inequity, and he counts mortality, effort and the unchosen character of what is given to us among those goods. He chaired the President's Council on Bioethics from 2001 to 2005 and is the most philosophically substantial exponent of Bioconservatism. Career Kass trained as a physician at the University of Chicago and took a doctorate in biochemistry at Harvard, working afterwards at the National Institutes of Health. He spent a summer in Mississippi during the civil rights movement, an experience he has described as formative in a different direction than expected: it made him doubt that scientific and material progress carries moral progress along with it. Reading Huxley's Brave New World alongside the emerging debates over reproductive technology completed the turn, and by the early 1970s he had left the laboratory for the study of ethics and political philosophy. He served as executive secretary of a National Academy of Sciences committee on the life sciences and social policy, taught at St John's College in Annapolis, and joined the University of Chicago's Committee on Social Thought in 1976, where he taught for more than three decades. He has been a fellow at the American E","c":["people","society"],"k":"person","x":"established","h":"present","w":1170,"n":11},{"s":"leonard-hayflick","t":"Leonard Hayflick","d":"American microbiologist who showed in 1961 that normal human cells divide a finite number of times in culture, and who argued for fifty years afterwards that aging is not a disease.","g":["aging","cellular senescence","biogerontology","cell culture","vaccines","hayflick limit"],"b":"Leonard Hayflick was an American microbiologist who reported in 1961 that normal human cells stop dividing after a limited number of divisions in culture, overturning a half-century belief that vertebrate cells were immortal if kept properly. The arrest he described became known as the Hayflick limit and is the origin of the field now called Cellular senescence. He spent the rest of his career insisting that his own discovery did not mean what the life-extension movement wanted it to mean, and was among the most prominent scientific critics of anti-aging commerce. Overview Hayflick holds an unusual position in this wiki. Almost every longevity programme covered here descends in some way from his 1961 result, and he rejected almost all of them. He held that aging is not a disease, that it is caused by the accumulation of molecular disorder rather than by a programme that could be switched off, and that no intervention had been shown to slow it in a person. Two of those three claims remain the mainstream view. The third, that no such intervention is likely, is where he parted from the field his work founded. Career Hayflick was born in Philadelphia in 1928 and took his doctorate at the University of Pennsylvania in 1956, followed by postdoctoral training in cell culture under Charles Pomerat at the University of Texas Medical Branch. He returned to Philadelphia and spent roughly ","c":["people","longevity"],"k":"person","x":"historical","h":"historical","w":1475,"n":1},{"s":"limb-regeneration","t":"Limb regeneration","d":"The regrowth of an amputated limb from the stump, routine in salamanders and absent in mammals, and the biology that separates the two.","g":["regeneration","axolotl","blastema","wound healing","bioelectricity","comparative biology"],"b":"Limb regeneration is the regrowth of a complete, correctly patterned limb after amputation. Salamanders do it repeatedly throughout life, replacing bone, muscle, nerve, vasculature and skin in the right proportions and at the right positions along the limb axis. Mammals do not. An amputated mammalian limb heals by inflammation, contraction and fibrosis, producing a scar rather than a structure. The gap has been studied for more than two centuries, and the question of whether it can be closed in humans remains open in the specific sense that nobody knows what the full list of missing ingredients is. What regeneration requires The salamander sequence is well characterized. Within hours of amputation, epidermal cells migrate over the wound to form a thin covering, without clotting or scab formation. This layer thickens into a signalling centre, the apical epithelial cap. Beneath it, cells from the stump (mainly connective tissue fibroblasts, along with satellite cells and Schwann cells) lose their differentiated character, re-enter the cell cycle, and accumulate into a mass called the blastema. The blastema proliferates, then repatterns itself into the missing structures from the amputation plane outward. Two features constrain the process. First, it is nerve-dependent: a denervated limb forms no blastema, and the requirement is quantitative, with a threshold density of axons need","c":["bodies","longevity"],"k":"concept","x":"experimental","h":"2050s+","w":1462,"e":"The only human structure known to regrow after amputation is the fingertip distal to the nail bed, most reliably in children; no mammalian limb has been regenerated by any intervention.","n":13},{"s":"lipid-nanoparticles","t":"Lipid nanoparticles","d":"Four-component lipid vesicles that carry mRNA and other nucleic acids into cells, the delivery system behind mRNA vaccines and the first systemic in vivo CRISPR therapies.","g":["delivery","mrna","gene therapy","crispr","nanomedicine","vaccines"],"b":"Lipid nanoparticles are small synthetic vesicles, typically 60 to 100 nanometres across, that package fragile nucleic acids and ferry them across a cell membrane. They are the reason mRNA vaccines work and the reason the first systemically delivered CRISPR therapy reached patients. Because they deposit their cargo overwhelmingly in the liver, they are also the reason most in vivo genome-editing programmes as of 2026 target a hepatic gene. Unlike Aav vectors, they carry no viral protein, provoke no lasting anti-vector immunity, and can be given more than once. How it works The active ingredient is the ionizable lipid. It carries an amine that is uncharged at blood pH, so the circulating particle is close to neutral and avoids the toxicity and rapid clearance that plagued the permanently cationic lipids of the 1990s. Inside the acidifying endosome, the amine picks up a proton. The now-positive lipid pairs with anionic endosomal phospholipids, destabilises the membrane, and lets a fraction of the RNA escape into the cytosol before the compartment matures into a lysosome and degrades the rest. The other three components are structural. A helper phospholipid, usually DSPC, and cholesterol set the particle's phase behaviour and rigidity; a polyethylene-glycol-conjugated lipid coats the surface, controls particle size during mixing, and slows opsonisation. The particles are made by ra","c":["genetics","nanomedicine"],"k":"technology","x":"established","h":"present","w":1313,"e":"Billions of mRNA vaccine doses and an approved siRNA drug establish that the carrier works and is tolerated in people, and a phase 1 trial showed a single infusion of an LNP-delivered CRISPR editor cut circulating transthyretin.","a":"Approved LNP products are in clinical use (mRNA vaccines at population scale, patisiran as an infused drug for a rare disease), while the genome-editing therapies using the same carrier are trial-only.","r":"context","n":37},{"s":"longevity-escape-velocity","t":"Longevity escape velocity","d":"The hypothetical threshold at which medicine adds remaining life expectancy faster than time subtracts it, making death by aging recede indefinitely.","g":["aging","forecasting","life extension","demography","biogerontology","mortality"],"b":"Longevity escape velocity (LEV) is the hypothetical point at which biomedical progress extends a person's remaining life expectancy by more than one year for every year that passes. Past that threshold the expected date of death recedes faster than the calendar advances, and death from age-related causes no longer has a scheduled date. Aubrey de grey named and popularized the term in the early 2000s. It is an arithmetic claim about rates of improvement and makes no claim that any particular therapy works. Overview Longevity escape velocity is a condition on the rate of change of a demographic quantity, not a technology, a therapy, or a date. Write e(x, t) for the remaining life expectancy of a person aged x in calendar year t. Someone alive today ages one year and simultaneously moves one year into the future of medicine, so their remaining life expectancy changes by the sum of two terms: a loss from being older, and a gain from a year of progress. Escape velocity is reached when the gain exceeds the loss and remaining life expectancy stops falling. Two consequences follow. First, the threshold is age-specific: a thirty-year-old loses very little remaining life expectancy per year of aging and clears the bar easily, while an eighty-five-year-old loses a great deal and may never clear it. Second, LEV does not require immortality, a cure for aging, or any single decisive result. ","c":["longevity","foundations"],"k":"concept","x":"speculative","h":"2050s+","w":1766,"e":"No intervention has been shown to slow human aging on a validated endpoint; gains in remaining life expectancy at older ages have run at roughly a year per decade, an order of magnitude short of the threshold.","n":33},{"s":"loyal","t":"Loyal","d":"A biotechnology company developing drugs to extend healthy lifespan in dogs, working through the veterinary regulator that will consider lifespan itself as an indication.","g":["aging","dogs","veterinary medicine","healthspan","regulation","igf-1","biotech"],"b":"Loyal is a San Francisco biotechnology company, incorporated in Delaware in 2019 as Cellular Longevity, Inc., that develops drugs intended to extend the healthy lifespan of dogs. Its founder, Celine Halioua, began her career at the Longevity Fund, the venture firm started by Laura Deming. Its interest for geroscience is procedural as much as pharmacological: the veterinary arm of the US Food and Drug Administration will entertain \"extension of lifespan\" as a drug indication, and its human counterpart will not. As of November 2026 the agency had accepted the effectiveness sections for all three of Loyal's drug candidates and the safety section for one, but had approved none of them, and no study had shown that a Loyal drug lengthens a dog's life. Overview The company's premise is that dogs are closer to people than laboratory mice are, and closer to a marketed product than any human aging drug. Companion dogs share human households, diets and sedentary habits. They develop cancer, osteoarthritis and a cognitive decline syndrome resembling dementia, and they are genetically diverse in a way inbred mouse colonies are not. They also die within about a decade, which makes a survival endpoint affordable. A trial powered on how long the animals live reads out in years, where a human equivalent would need decades; that arithmetic is what pushed the proposed TAME trial in people onto a ","c":["organizations","longevity"],"k":"organization","x":"emerging","h":"late 2020s","w":2563,"n":7},{"s":"machine-consciousness","t":"Machine consciousness","d":"The question of whether an artificial system can have subjective experience, how anyone could tell, and what would follow morally if one did.","g":["consciousness","artificial intelligence","moral status","functionalism","ai welfare","philosophy of mind"],"b":"Machine consciousness is the question of whether an artificial system can have subjective experience (whether there is something it is like to be it), together with the derived questions of how anyone could establish this and what obligations would follow. It is distinct from machine intelligence. A system can solve problems, model the world, and describe its own states without any of that entailing experience, and the two properties can in principle come apart in either direction. Why behaviour underdetermines the answer Alan Turing set consciousness aside deliberately, replacing \"can machines think\" with a test of conversational indistinguishability and noting that the same solipsistic worry applies to other people. The move was productive for artificial intelligence and unhelpful here: with humans, an inference from behaviour to experience is supported by shared physiology and evolutionary history, and neither support is available for an artificial system. Errors run in both directions. People over-attribute minds readily: Joseph Weizenbaum's ELIZA elicited emotional disclosure from users who knew it was a pattern-matching script, and the effect has scaled with fluency. In 2022 a Google engineer publicly claimed that a conversational model was sentient, a claim the company rejected and which most researchers read as a demonstration of the attribution problem rather than evid","c":["minds"],"k":"concept","x":"speculative","h":"indefinite","w":1469,"n":16},{"s":"magnesium-l-threonate","t":"Magnesium L-threonate","d":"A magnesium salt of a vitamin C breakdown product, sold as Magtein, that raised brain magnesium and memory in rats and has small, industry-funded human trials.","g":["cognition","supplements","magnesium","memory","sleep","dementia"],"b":"Magnesium L-threonate (MgT, also called L-threonic acid magnesium salt or L-TAMS) is a magnesium salt of L-threonic acid, a breakdown product of vitamin C, sold under the brand name Magtein as a supplement for memory and sleep. It was developed by the neuroscientist Guosong Liu and colleagues, whose 2010 study in rats reported that it raised brain magnesium where ordinary magnesium supplements did not, and improved learning and memory. The human evidence consists of a handful of small, short trials, and every placebo-controlled trial of cognition or sleep has been funded by a company that sells the ingredient. How it works Inside neurons, magnesium blocks the channel of the NMDA receptor, a glutamate receptor central to synaptic plasticity, in a voltage-dependent way. Liu's hypothesis is that raising magnesium inside neurons increases the number of functional synapses and makes plasticity more selective. In the founding study, rats given MgT orally performed better on tests of learning, working memory and short- and long-term memory, and aged rats improved on a pattern-completion task. Treated rats had a higher density of presynaptic markers in two hippocampal subregions, and the density correlated with memory performance. Contemporary coverage reported that MgT raised magnesium in the rats' cerebrospinal fluid by 7 to 15 percent after 24 days, while most other oral magnesium c","c":["enhancement","longevity"],"k":"intervention","x":"experimental","h":"present","w":1403,"e":"Four small placebo-controlled trials, one of a multi-ingredient formula and each funded by a company selling the ingredient, report modest gains on cognitive or sleep measures over 3 to 12 weeks; brain uptake is shown only in rats.","a":"Sold without prescription as a dietary supplement in the United States and authorised in the EU as a novel food ingredient in 2024; the ingredient is patented and licensed under the Magtein brand.","r":"reversible","n":2},{"s":"max-more","t":"Max More","d":"British-American philosopher who founded extropianism, wrote the principles that gave transhumanism its first organized programme, and led Alcor from 2011 to 2020.","g":["transhumanism","extropianism","cryonics","philosophy","proactionary principle"],"b":"Max More is a British-American philosopher who first stated Transhumanism systematically as a philosophy rather than a collection of enthusiasms. His 1990 essay defined the term in its modern sense, his Principles of Extropy set out the movement's working commitments, and the Extropy Institute and its mailing list were the organizing node for early transhumanist thought. From 2011 to 2020 he was chief executive of the Alcor Life Extension Foundation. Career Born Max T. O'Connor, he read philosophy, politics and economics at Oxford, where he was involved in early British cryonics organizing, and moved to the United States for graduate work in philosophy at the University of Southern California. In 1990 he changed his surname to a word that named what he was arguing for. His doctorate, completed in 2010, was on the nature of death and the conditions for personal survival, the philosophical question beneath the practice he would later run as a business. See Personal identity and continuity. With Tom W. Bell he founded the magazine Extropy in 1988 and the Extropy Institute in 1992. The institute ran conferences through the 1990s and closed in 2006. More's stated reason was that its ideas had propagated into enough other organizations that a dedicated body was no longer needed. He co-edited The Transhumanist Reader (2013) with Natasha vita more, to whom he is married. The Principles","c":["people"],"k":"person","x":"established","h":"present","w":917,"n":11},{"s":"maximum-human-lifespan","t":"Maximum human lifespan","d":"The longest duration a human being has lived or could live, distinct from average life expectancy and disputed as to whether any fixed ceiling exists.","g":["aging","demography","mortality","supercentenarians","life extension"],"b":"Maximum human lifespan is the greatest age a human being has attained or, in its theoretical sense, the greatest age a human could attain under the best achievable conditions. It is a property of the extreme tail of the mortality distribution and behaves very differently from life expectancy, which is a mean. Whether the species has a fixed ceiling, and if so where, has been argued in the demographic literature since the 1990s without resolution. Lifespan and life expectancy The two quantities are routinely confused. Life expectancy at birth is the mean age at death of a hypothetical cohort experiencing current age-specific mortality rates. It has risen dramatically over two centuries, mostly because fewer people die young. Maximum lifespan is a record, an order statistic drawn from the extreme right tail, and it responds far less to public-health improvement. Saving infants does not lengthen the tail; it only sends more people into it. The distinction disciplines several common arguments. Classical claims that Bronze Age humans lived to 30 describe an average dragged down by infant mortality, not a species whose members died at 30. It also explains why record ages have crept upward far more slowly than mean ages: the tail grows because the population at risk grows, not because the biology has changed. A third quantity, Healthspan, tracks the years lived in good function and mo","c":["longevity"],"k":"concept","x":"contested","h":"indefinite","w":2562,"n":23},{"s":"microrobots-in-medicine","t":"Medical microrobots","d":"Micrometre- to millimetre-scale devices steered through the body by external magnetic, acoustic, or biological means, demonstrated in animals and used clinically only as capsule endoscopes.","g":["nanomedicine","microrobots","magnetic steering","drug delivery","biohybrid","imaging"],"b":"Medical microrobots are small untethered devices, from a few micrometres to a few millimetres across, that are moved through the body by fields applied from outside it and made to deliver a drug, remove material, or take a measurement. They differ from the machines described in Medical nanorobots in two ways. They are larger by three to six orders of magnitude in volume, and they carry no intelligence: decisions are made by an operator or a control algorithm outside the patient. Those differences make them a real engineering discipline with working prototypes rather than a design tradition, and they also make them much less capable than the devices the Molecular assembler literature imagines. How it works Propulsion at this scale is governed by viscosity. A body a few micrometres across in water has a Reynolds number around 10⁻⁵, meaning inertia contributes nothing and any motion that reverses itself exactly produces no net displacement. Effective swimmers must therefore break time-reversal symmetry. The dominant design is accordingly a helix rotated by an external field: a corkscrew turning in a viscous fluid advances, and reversing the rotation reverses the direction. Magnetic actuation splits into two regimes. Pulling a device with a field gradient produces a force proportional to the device's volume, so it works for millimetre-scale objects and becomes useless as the device","c":["nanomedicine","bodies"],"k":"technology","x":"experimental","h":"2030s","w":1504,"e":"The only such devices used in people are centimetre-scale magnetically steered capsule endoscopes; every therapeutic result comes from animals, flow models, or extracted tissue.","a":"Magnetic capsule endoscopy is offered as a clinical procedure in several countries; no therapeutic microrobot is approved or purchasable anywhere.","r":"context","n":11},{"s":"medical-nanorobots","t":"Medical nanorobots","d":"Proposed micron-scale machines that would circulate in the body and perform mechanical repair, a design tradition with no working device and several unsolved physical constraints.","g":["nanomedicine","nanorobotics","drug delivery","molecular machines","dna origami","microrobots"],"b":"Medical nanorobots are hypothetical machines, roughly the size of a virus or a small bacterium, that would circulate in the body and perform mechanical work on it: clearing a plaque, digesting a pathogen, replacing a chromosome, reporting on a tissue's state. No such device exists as of 2026, and none is in clinical trials. What exists is a set of much simpler objects that the popular literature often calls nanorobots: passive drug-carrying particles, DNA structures that spring open when they meet a molecular signal, and micron-scale swimmers steered from outside the body by magnetic fields. The design tradition The lineage starts with a lecture. In 1959 Richard Feynman told the American Physical Society that nothing in physics forbade manipulating matter atom by atom, and relayed a suggestion from his colleague Albert Hibbs that one might one day \"swallow the surgeon\", meaning a machine small enough to travel to a diseased site and operate there. The idea sat mostly dormant for twenty-five years. Eric drexler revived it as an engineering programme. Engines of Creation (1986) described a world in which programmable molecular assemblers build atomically precise devices, including cell-repair machines that would enter tissue, identify damage, and correct it. Nanosystems (1992) supplied the quantitative case: bearings, gears, and computers built from diamondoid carbon lattices, an","c":["nanomedicine"],"k":"technology","x":"speculative","h":"2050s+","w":1964,"e":"No medical nanorobot has been given to a person; the nearest devices, DNA origami containers with molecular latches, have been demonstrated in cell culture and in mice.","a":"Nothing to obtain: no such device exists outside design studies, and the approved products marketed as nanomedicine are passive drug formulations rather than machines.","r":"difficult","n":23},{"s":"memory-prosthesis","t":"Memory prosthesis","d":"An implanted device intended to restore or improve memory formation by supplying the pattern of neural activity a damaged or underperforming hippocampus fails to generate.","g":["memory","hippocampus","implants","cognitive enhancement","closed-loop","neuroethics"],"b":"Memory prostheses are devices intended to improve or restore the formation of new memories. They record activity in the hippocampal circuit, compute what the healthy circuit would have produced, and deliver that pattern back as electrical stimulation. The concept is the only serious attempt at a cognitive neuroprosthesis, as distinct from the sensory and motor devices that dominate Neuroprosthetics. As of 2026 it exists as a set of within-session experiments in patients who already have electrodes implanted for epilepsy surgery, with reported effects on laboratory memory tasks and no chronic device in anyone. The idea Sensory and motor prostheses substitute for a transmission path. A Cochlear implant replaces a transducer, and a motor Brain computer interface carries a command around a broken spinal cord. Neither has to reproduce a computation. Memory is different. The hippocampus transforms the signals it receives instead of relaying them, converting patterns of cortical input into the sparse, distributed codes that support later recall. A memory prosthesis must therefore reproduce a transformation rather than a channel. Theodore Berger's group posed the problem in exactly those terms: model the input-output function of the CA3-to-CA1 projection well enough to predict, from observed CA3 firing, what CA1 should do, then stimulate CA1 accordingly when the natural pathway fails. ","c":["cybernetics","minds"],"k":"technology","x":"experimental","h":"2040s","w":1355,"e":"Within-session experiments in small numbers of epilepsy patients carrying temporary depth electrodes report better recall on laboratory tasks; no person has ever had a chronic memory implant.","a":"Not obtainable on any terms: the work exists only inside research protocols that use electrodes implanted for epilepsy surgery, and no memory prosthesis is approved or sold anywhere.","r":"difficult","n":22},{"s":"mental-privacy","t":"Mental privacy","d":"The question of what can be inferred about a person's mental states from neural and physiological recordings, and what protection that information should receive.","g":["privacy","neural data","decoding","surveillance","law","eeg"],"b":"Mental privacy is the interest a person has in controlling what others can learn about their thoughts, intentions, and internal states from measurements of the brain and body. It is the most-invoked of the proposed Neurorights, and the one where public expectation and technical reality diverge most. No device can read an uncooperative person's thoughts, and the systems that infer the most about mental life mostly do not record from the brain at all. What non-invasive recording can do Functional magnetic resonance imaging measures blood-oxygenation changes on a timescale of seconds, which is orders of magnitude slower than neural firing. Within that limit, the statistical methods surveyed in Neural decoding have achieved results that would have seemed impossible in 2010, provided the decoder is trained on the individual whose brain it will read. The clearest demonstration is a 2023 study in which a language model was used to reconstruct the approximate meaning of stories a participant heard, imagined, or watched while in the scanner. The output was a paraphrase rather than a transcript: the decoder recovered gist, not words. Three constraints on the result matter more than the result itself. Each decoder required roughly sixteen hours of scanner time with that specific participant. Decoders did not transfer across people. The authors also tested resistance directly: participants","c":["society","cybernetics","minds"],"k":"concept","x":"emerging","h":"late 2020s","w":1420,"n":26},{"s":"metformin","t":"Metformin and the TAME trial","d":"A generic diabetes drug proposed as a geroprotector, and the large randomized trial designed to make aging itself an acceptable regulatory indication.","g":["metformin","aging","clinical trials","drug repurposing","regulation","diabetes"],"b":"Metformin and the TAME trial are, respectively, the most widely prescribed oral diabetes drug in the world and the study designed to test whether it delays the onset of age-related disease in people who do not have diabetes. The pairing matters beyond the drug. TAME was built chiefly as a regulatory experiment: an attempt to get a health authority to accept a composite of age-related diseases as a legitimate trial endpoint, and so to make aging a drug indication. As of 2026 the trial has not been funded at the scale it requires and has not enrolled, and the evidence that metformin slows human aging remains observational and contested. Origins of the claim Metformin derives from guanidine compounds found in Galega officinalis and entered clinical use in France in 1957. Its geroprotective reputation rests largely on a 2014 observational analysis reporting that people with type 2 diabetes taking metformin survived slightly longer than matched controls without diabetes. The finding drew attention because diabetes shortens life; a drug that erased and reversed that penalty would be doing something beyond glucose control. The result has not held up cleanly. Comparisons of this kind are vulnerable to immortal-time bias, confounding by indication and healthy-adherer effects, and several reanalyses have argued that the survival advantage weakens or disappears once these are handled prop","c":["longevity"],"k":"intervention","x":"contested","h":"2030s","w":1282,"e":"The geroprotective case in people is observational, drawn from diabetes prescribing records; no randomized trial has tested a composite age-related endpoint, and two trials in older adults found it blunted the response to exercise training.","a":"A generic prescription drug approved worldwide for type 2 diabetes and costing a few dollars a month; no regulator has approved it for aging, so any such use is off-label.","r":"reversible","n":33},{"s":"methuselah-foundation","t":"Methuselah Foundation","d":"A Virginia nonprofit founded in the early 2000s that used prize competitions to seed research on life extension, regenerative medicine and organ engineering.","g":["aging","prizes","nonprofit","tissue engineering","organ preservation","research funding"],"b":"Methuselah Foundation is a nonprofit organization founded in the early 2000s by the entrepreneur David Gobel and the biogerontologist Aubrey de grey to accelerate research on extending healthy human life, principally by running prize competitions. Its stated mission is to \"make 90 the new 50 by 2030\". It is best known for the Mprize, which rewarded record-setting mouse longevity, and for the New Organ prizes in regenerative medicine, and it spun out the Sens research foundation in 2009. Overview The foundation's method is deliberate. It identifies a bottleneck, defines a measurable target, and offers money for hitting the target rather than for proposing to try. Prizes shift the risk from funder to competitor, attract entrants a grant committee would not select, and produce a public benchmark. They work only where the target is unambiguous, however, and that has constrained what the foundation could take on. Its second function has been convening. For most of the 2000s, when aging research attracted little private money, the foundation was one of very few places where researchers, donors and advocates in the field met at all, and a substantial share of the modern longevity field traces back to those connections. The Mprize The Methuselah Mouse Prize, launched in 2003 and usually shortened to the Mprize, is the organization's signature programme. It awarded money in two categori","c":["organizations","longevity"],"k":"organization","x":"established","h":"present","w":1212,"n":7},{"s":"microgravity-adaptation","t":"Microgravity adaptation","d":"The set of physiological and neural changes by which the human body reorganises itself for weightlessness, and the countermeasures that limit the cost of returning.","g":["microgravity","spaceflight","vestibular","bone loss","countermeasures","artificial gravity"],"b":"Microgravity adaptation is the process by which the human body reconfigures itself for an environment without a gravitational reference. The vestibular system reinterprets its own signals, the cardiovascular system resets around a lost hydrostatic gradient, and bone and muscle remodel to the mechanical loads actually being applied, which are almost none. The changes are largely appropriate to weightlessness and largely unhelpful on return. Most of what happens in orbit is therefore adaptation rather than damage, and the clinical problem arrives at the other end. Sensorimotor and vestibular reorganisation The otolith organs of the inner ear detect linear acceleration, and on Earth the constant 1 g field lets the brain read otolith output as head tilt. In free fall that inference breaks. Otolith signals no longer correlate with orientation, while the semicircular canals continue to report rotation normally. The mismatch is the standard explanation for space motion sickness, which affects a majority of crew members in the first days of flight and usually resolves within about three days. What follows is neural plasticity. The brain reweights vestibular input against vision and proprioception, and by the end of the first week most crew move competently in a volume with no floor. Reaching, gaze stabilisation, and head-eye coordination all recalibrate. The reweighting belongs to the ","c":["space","bodies"],"k":"concept","x":"established","h":"present","w":1520,"e":"Measured directly in astronauts across decades of orbital flight and reproduced on the ground by head-down bed rest; no human data exist for sustained exposure to gravity between zero and one.","n":8},{"s":"mind-uploading","t":"Mind uploading","d":"The hypothetical transfer of a person's mind to a computational substrate, such that the resulting process is that person rather than a description of them.","g":["uploading","emulation","identity","consciousness","brain preservation","functionalism"],"b":"Mind uploading is the hypothetical transfer of a person's mental life onto a non-biological substrate, usually a computer, such that the resulting process has that person's memories and personality and, on the strong version of the claim, that person's continued experience. It combines a technical proposal, Whole brain emulation, with a philosophical claim about what makes a future being the same person as an earlier one. The two components fail independently: the emulation could work while the person does not survive it, and the identity argument could be correct while the engineering never arrives. Overview Discussion of uploading tends to collapse three separable questions. First, can a computational model of a specific brain be built and run so that it behaves as the original would? That is an empirical question about scanning, modelling, and computation. Second, would such a model be conscious, in the sense that there would be something it is like to be it? That depends on unsettled theory, treated under Machine consciousness and Neural correlates of consciousness. Third, if the model is conscious, is it the original person or a very good imitation? That is a question in Personal identity and continuity, and it is not answerable by measurement. Advocates generally hold that the answers are yes, yes, and yes, resting on Substrate independence, the view that mental states de","c":["minds"],"k":"concept","x":"speculative","h":"2050s+","w":1791,"n":26},{"s":"mirror-life","t":"Mirror life","d":"Hypothetical organisms built from mirror-image biological molecules, which a large group of scientists argued in 2024 could evade immunity and predation and should not be created.","g":["synthetic biology","biosafety","chirality","moratorium","governance","catastrophic risk"],"b":"Mirror life refers to hypothetical organisms constructed from the mirror images of ordinary biological molecules: proteins built from D-amino acids rather than L, and nucleic acids built from L-sugars rather than D. No such organism exists, and none is close to existing. In December 2024 a group of thirty-eight scientists, drawn from synthetic biology, immunology, ecology and biosecurity, published a warning in Science arguing that mirror bacteria would be uniquely dangerous and that work toward creating them should not proceed. The argument turns on a structural fact about biology rather than on any specific pathogen. Chirality in biology Most biological molecules are chiral: they exist in two forms that are mirror images and cannot be superimposed, like left and right hands. Life on Earth uses one hand almost exclusively. Proteins are built from L-amino acids; DNA and RNA use D-ribose and D-deoxyribose. The choice appears to be a frozen accident, since the chemistry works identically either way, and a complete mirror organism would in principle be viable. That uniformity underlies nearly every molecular recognition event in biology. Enzymes are chiral surfaces that fit chiral substrates. Antibodies bind shapes. Receptors, transporters and proteases all discriminate by handedness. A protein made of D-amino acids folds into the mirror image of the normal structure and is, to al","c":["genetics","society"],"k":"risk","x":"speculative","h":"2050s+","w":1536,"e":"No mirror organism exists, so no person has ever been exposed to one; the nearest human exposure is to mirror-image molecules, such as the L-configured aptamers taken into clinical trials as Spiegelmers.","a":"Nothing to obtain: no mirror organism exists anywhere, and the peptide chemistry needed to build one is far beyond current capability.","r":"irreversible","n":16},{"s":"mitochondrial-dysfunction","t":"Mitochondrial dysfunction in aging","d":"Age-related decline in mitochondrial energy production, quality control and signalling, once explained by free-radical damage and now understood as a more tangled process.","g":["aging","mitochondria","oxidative stress","mtdna","metabolism","mechanisms"],"b":"Mitochondrial dysfunction in aging refers to the progressive loss of mitochondrial respiratory capacity, genome integrity and quality control that accompanies age in most tissues studied. The Hallmarks of aging framework classes it as an antagonistic hallmark, meaning that the underlying responses protect at low intensity and do damage when chronic. The mechanism was long assumed to be self-amplifying oxidative damage, an explanation that has not survived the experiments designed to test it. What declines Mitochondria generate most cellular ATP through oxidative phosphorylation. They also buffer calcium, synthesize iron-sulfur clusters and steroid hormones, and control the intrinsic apoptosis pathway. Each carries multiple copies of a circular genome of roughly 16.5 kilobases encoding 37 genes, 13 of which are protein subunits of the respiratory chain; the remaining thousand-odd mitochondrial proteins are encoded in the nucleus and imported. With age, measured respiratory capacity per unit of mitochondrial mass falls in muscle, liver and brain. Mitochondrial morphology becomes more heterogeneous, membrane potential declines in a subset of organelles, and damaged mitochondria are cleared more slowly. Aged human skeletal muscle contains individual fibres that lack cytochrome c oxidase activity, each traceable to a clonally expanded mitochondrial DNA deletion. Comparable clonal ex","c":["longevity"],"k":"concept","x":"established","h":"present","w":1167,"e":"Falling respiratory capacity and clonally expanded mtDNA deletions are documented in aged human muscle and brain tissue; antioxidant trials in people found no mortality benefit and signals of harm.","n":23},{"s":"mitochondrial-replacement-therapy","t":"Mitochondrial replacement therapy","d":"A set of IVF techniques that place a mother's nuclear DNA in a donor egg to prevent transmission of mitochondrial DNA disease, licensed in a few countries and used rarely.","g":["reproduction","mitochondria","ivf","germline","regulation","heteroplasmy"],"b":"Mitochondrial replacement therapy is a group of in vitro fertilisation techniques that combine the nuclear DNA of a prospective mother with the cytoplasm, and therefore the mitochondria, of a donor egg. The purpose is to prevent a child from inheriting a pathogenic mutation in mitochondrial DNA. It is the only form of heritable human genetic modification any country has legalised, and only a small number of children worldwide have been born from it. The disease it addresses Mitochondria carry their own small circular genome of about 16,500 base pairs, which encodes thirteen proteins of the respiratory chain plus the RNAs needed to make them. It is inherited almost exclusively from the egg. Mutations in it cause a heterogeneous group of disorders, among them Leigh syndrome, MELAS, MERRF and Leber's hereditary optic neuropathy. They typically affect tissues with high energy demand, such as brain, heart, skeletal muscle and retina. Inheritance is complicated in two ways. Cells carry many mitochondrial genomes, so a person can be heteroplasmic, carrying a mixture of normal and mutant copies. Most mitochondrial diseases also show a threshold effect, in which symptoms appear only above a high mutant fraction, often well over half. During oogenesis a genetic bottleneck randomly samples a small number of mitochondrial genomes to seed each egg, so a heteroplasmic mother's eggs vary wide","c":["reproduction","genetics"],"k":"intervention","x":"emerging","h":"present","w":1498,"e":"Children have been born after the procedure in several countries; the largest reported series is eight UK births, with the mother's pathogenic mtDNA undetectable or below disease thresholds and follow-up still short.","a":"Licensed case by case in the UK and permitted on a staged pathway in Australia, blocked in the US by an appropriations rider, and sold for infertility by clinics in countries with no specific rules.","r":"irreversible","n":12},{"s":"molecular-assembler","t":"Molecular assembler","d":"A proposed machine that would build objects by positioning individual atoms, central to Drexler's nanotechnology programme and disputed by chemists since the 1990s.","g":["nanotechnology","mechanosynthesis","manufacturing","molecular machines","drexler","chemistry"],"b":"A molecular assembler is a hypothetical machine that would build structures by holding and positioning individual reactive molecules, bonding them to a workpiece one at a time under programmed control. The idea is the foundation of Eric drexler's nanotechnology programme and, by extension, of the entire design literature on Medical nanorobots. No assembler has been built, and whether the central chemical step is achievable at all has been argued for three decades without an experimental resolution. Overview Ordinary chemistry mixes reagents in solution and lets thermal motion bring them together, so which products form is a matter of statistics and energetics. Mechanosynthesis proposes the opposite: hold a reactive group on a stiff tool, bring it to a specific site on a workpiece, force the reaction, and withdraw. The output would be an atomically precise structure specified in advance rather than a statistical distribution of products. Drexler argued in Nanosystems that machines to do this could be built from diamondoid components, stiff carbon lattices whose behaviour can be modelled with classical mechanics, and he analysed their bearings, gears, drive trains, and error rates quantitatively. The book is a work of theoretical engineering. It contains no experiments and says so carefully. Most of the controversy that followed turns on generality and throughput. An assembler th","c":["nanomedicine"],"k":"concept","x":"contested","h":"indefinite","w":1561,"n":10},{"s":"moral-enhancement","t":"Moral enhancement","d":"The proposal to improve human moral motivation by biomedical means, argued for as a response to technologies that outpace evolved moral psychology.","g":["ethics","enhancement","psychopharmacology","autonomy","existential risk","bioethics"],"b":"Moral enhancement is the proposal to improve human moral dispositions, such as altruism, impartiality and aversion to causing harm, by biomedical intervention rather than by education or institutional design. It is the branch of Human enhancement whose advocates present it as a response to a mismatch rather than as an optional improvement: a moral psychology shaped for small groups now controls technologies capable of catastrophic harm. Critics reply that the psychopharmacology on offer is far too crude for the job, and that the interventions proposed would damage something essential to moral agency even if they worked. The argument Ingmar Persson and Julian savulescu set out the case in a 2008 paper and expanded it in Unfit for the Future. The argument has four steps. Human moral psychology evolved under conditions of small-group cooperation. It is biased toward kin and near neighbours, toward the immediate over the distant future, and toward acts over omissions. Those biases were adaptive and are now liabilities. Technology has made the harm a small number of people can cause vastly greater than the good a comparable number can do. Persson and Savulescu call the worst case ultimate harm, meaning an outcome that permanently destroys the prospect of a worthwhile life on Earth. The relevant class of hazards is the one described in Existential risk and, for the biological cases, ","c":["enhancement","society"],"k":"concept","x":"speculative","h":"indefinite","w":1471,"e":"No agent has been shown to change how a person actually treats anyone; every human result is a shift on a questionnaire or a laboratory task, measured in a single session in healthy volunteers.","n":9},{"s":"morphological-freedom","t":"Morphological freedom","d":"The claimed right to modify one's own body and mind as one chooses, and the correlative right to refuse modification imposed by others.","g":["autonomy","rights","bodily integrity","enhancement","law","ethics","cosmetic surgery"],"b":"Morphological freedom is the claim that a person has a right to alter their own body and mind, whether chemically, surgically, genetically or electronically, and an equally strong right not to be altered by anyone else. It is the political principle most closely associated with Transhumanism, and its advocates regard it as the one doing the real work, because it makes no claim that enhancement is good, only a claim about who decides. Origins Max more introduced the phrase in a 1993 essay in Extropy, defining it as the ability to alter bodily form at will through technologies such as surgery, genetic engineering, nanotechnology and uploading. The formulation was libertarian in spirit and framed as an extension of self-ownership. Anders sandberg gave the idea its most-cited treatment in a paper presented at a transhumanist conference in 2001. His argument runs from the right to life and the right to one's own body: if these are meaningful, they include the right to change what one is made of, since a right to a body one may not modify is a right to a cage. Sandberg's more consequential move was to insist that the right is symmetrical. Morphological freedom includes the right to remain unmodified, so it defends against coerced enhancement as well as licensing enhancement, and that symmetry distinguishes the position from a simple pro-technology stance. The argument The positive ca","c":["society","enhancement"],"k":"concept","x":"contested","h":"present","w":1906,"n":31},{"s":"myoelectric-prosthetics","t":"Myoelectric prosthetics","d":"Externally powered artificial limbs controlled by electrical activity recorded from the wearer's residual muscles, the dominant design for powered upper-limb prostheses.","g":["prosthetics","amputation","emg","assistive technology","rehabilitation","sensory feedback"],"b":"Myoelectric prosthetics are artificial limbs driven by motors and controlled by the electrical activity of the wearer's own remaining muscles. Surface electrodes in the socket pick up electromyographic signals a few hundred microvolts in amplitude, the prosthesis converts their envelope into motor commands, and the user learns to produce the required contractions. The approach dominates powered upper-limb prosthetics. Modern hands are mechanically excellent, and the approach's persistent problem is the narrow, noisy control channel available to drive them. How it works Muscle fibres depolarize when they contract, and the summed extracellular field of many motor units is detectable through the skin. A pair of differential electrodes pressed against a residual muscle records this signal; the prosthesis rectifies and smooths it into an amplitude envelope and maps that envelope onto a motor's velocity. Squeeze harder and the hand closes faster. The classical arrangement is two-site proportional control: one electrode over a flexor group, one over an extensor group, driving a single degree of freedom in opposite directions. A wrist rotator or elbow requires switching modes, usually by co-contracting both muscles or by holding a contraction past a timeout. Each additional joint therefore costs the user a deliberate, non-intuitive switching action, which is why devices with five actua","c":["bodies","cybernetics"],"k":"technology","x":"established","h":"present","w":1391,"e":"Routine clinical care in human amputees since the 1960s; a randomized trial supports targeted muscle reinnervation for neuroma pain rather than for control, and osseointegrated implanted-electrode arms have been used at home by a small number of patients.","a":"Commercially available and fitted through prosthetics clinics in high-income countries; advanced hands run to tens of thousands of dollars before socket and therapy, and reimbursement varies sharply between health systems.","r":"partly-reversible","n":10},{"s":"myostatin-inhibition","t":"Myostatin inhibition","d":"Blockade of the growth factor myostatin to increase skeletal muscle mass, an effect reproduced across species that has repeatedly failed to translate into functional benefit in humans.","g":["muscle","sarcopenia","enhancement","gene therapy","clinical trials","follistatin"],"b":"Myostatin inhibition is the blockade of myostatin, a secreted protein that restrains skeletal muscle growth, in order to increase muscle mass. Animals lacking functional myostatin are visibly and dramatically muscular, and the finding has been reproduced in cattle, dogs, sheep, mice and at least one human child. Two decades of clinical development have shown that the mass gain transfers to human patients and that the functional benefit usually does not. That gap between bigger muscle and better muscle is the central fact of the field. How it works Myostatin, also called growth differentiation factor 8, is a member of the transforming growth factor β superfamily secreted by skeletal muscle itself. It circulates as a latent complex, is activated by proteolysis, and binds the activin type II receptor ActRIIB. Signalling through the type I receptors ALK4 and ALK5 phosphorylates Smad2 and Smad3, which suppresses the transcriptional programme for muscle protein synthesis and antagonises the Akt-mTOR pathway that drives hypertrophy. The system is a negative feedback brake, in which muscle produces the signal that limits its own growth. Interventions act at every point in that chain. - Antibodies against myostatin or against its latent precursor neutralise the ligand. - Antibodies or ligand traps against ActRIIB block the receptor, which also blocks activin A and other ligands that use","c":["enhancement","bodies"],"k":"intervention","x":"experimental","h":"late 2020s","w":1320,"e":"Antibody trials in muscular dystrophy and inclusion body myositis raised lean mass but missed functional endpoints; one reported a positive phase 3 in spinal muscular atrophy, and the huge-muscle phenotypes come from lifelong gene loss, not adult dosing.","a":"No approved product: the spinal muscular atrophy antibody was still under United States regulatory review as of mid-2026, while follistatin gene-transfer constructs are sold to individuals by ventures sited beyond the reach of drug regulators.","r":"context","n":17},{"s":"nad-precursors","t":"NAD+ precursors","d":"Supplements such as nicotinamide riboside and NMN that raise cellular NAD+ levels, with strong pharmacokinetic evidence and weak evidence of any functional benefit.","g":["nad","sirtuins","supplements","aging","metabolism","regulation"],"b":"NAD+ precursors are compounds, chiefly nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN), taken to raise cellular levels of nicotinamide adenine dinucleotide, a coenzyme that carries electrons in metabolism and is consumed as a substrate by several classes of enzyme. The rationale is that NAD+ declines with age in at least some tissues and that restoring it should restore the activity of the enzymes that depend on it. The supplements do raise NAD+ in blood reliably; whether that produces any benefit in humans is unresolved, and the field's commercial intensity considerably exceeds its evidence. The biology NAD+ has two distinct jobs. As a redox cofactor it cycles between NAD+ and NADH without being consumed, shuttling electrons through glycolysis and the mitochondrial electron transport chain. As a substrate it is destroyed: sirtuins cleave it to remove acyl groups from proteins, PARP enzymes consume it while responding to DNA damage, and the ectoenzyme CD38 degrades it outright. The second role is what links NAD+ to aging, because the consuming enzymes are all more active in aged tissue: more DNA damage means more PARP activity, and CD38 rises with the immune activation characteristic of Inflammaging and with the accumulation of senescent cells. Falling NAD+ availability is usually placed downstream of genomic instability and upstream of mitochondrial decline in","c":["longevity"],"k":"intervention","x":"contested","h":"present","w":1152,"e":"Oral nicotinamide riboside reproducibly raises blood NAD+ in human trials; no trial has shown a functional benefit in healthy older adults, and the results on mitochondria and stem cell decline come from mice.","a":"Nicotinamide riboside is sold freely as a dietary supplement in the United States; NMN's supplement status there is disputed and major retailers delisted it, and clinics sell intravenous NAD+ infusions direct to consumers.","r":"reversible","n":16},{"s":"naked-mole-rat","t":"Naked mole-rat","d":"A small eusocial African rodent whose flat mortality curve, tumour resistance and anoxia tolerance make it comparative biogerontology's central model organism.","g":["aging","comparative biology","cancer resistance","model organism","mortality","biogerontology"],"b":"The naked mole-rat (Heterocephalus glaber) is a small subterranean rodent of the Horn of Africa and comparative biogerontology's central example of negligible senescence: a mammal whose measured risk of dying does not climb with age. It lives roughly ten times longer than a mouse of similar size, resists spontaneous tumours, and survives oxygen deprivation that kills other mammals within minutes. Each of those traits has a proposed mechanism and a body of laboratory work behind it, but none has yet produced an intervention tested in people. The animal Naked mole-rats live in sealed burrow systems in the arid soils of Somalia, Ethiopia and Kenya, in colonies of tens to a few hundred animals. They are eusocial: a single female breeds, and the rest of the colony is reproductively suppressed and divided into castes that dig, forage and defend. Jennifer Jarvis described the arrangement in 1981, the first time eusociality had been documented in a mammal. They are hairless, effectively blind, and poikilothermic: body temperature follows the burrow instead of being held against it. What matters is the mismatch between size and lifespan. A 35-gram rodent would be expected to live a few years; captive naked mole-rats have exceeded thirty, several times longer than allometry predicts for their mass and far beyond any other rodent. That gap drew biogerontology to the species, and it is why","c":["longevity","foundations"],"k":"concept","x":"established","h":"present","w":1561,"e":"No naked mole-rat-derived intervention has been tested in people; the only lifespan result outside the species is in transgenic mice.","n":1},{"s":"nanoparticle-diagnostics","t":"Nanoscale diagnostics","d":"Detection methods that read single molecules or use nanoscale labels, including liquid biopsy, multi-cancer blood tests, and nanopore sensing, together with their overdiagnosis costs.","g":["nanomedicine","diagnostics","liquid biopsy","cancer screening","nanopore","biomarkers"],"b":"Nanoscale diagnostics covers detection methods that operate on individual molecules or use nanoscale particles as labels and sensors. The category runs from the mundane to the frontier. The coloured line on a home antigen test is a stripe of gold nanoparticles, while single-molecule sequencing through an engineered pore reads a DNA strand base by base. As of 2026 the branch with the most clinical consequence is the blood test for fragments of tumour DNA, which is closer to changing cancer screening than any other technology in this wiki's nanomedicine section. Nanoparticle labels The oldest working application uses nanoparticles as visible or magnetic reporters. Colloidal gold conjugated to antibodies aggregates at a capture line on a nitrocellulose strip and produces the red band of a lateral flow test. The format is cheap, needs no instrument, and was manufactured in billions of units during the COVID-19 pandemic. Superparamagnetic iron oxide particles are used as magnetic resonance contrast agents. In one cleared platform they are also the readout for detecting bloodstream pathogens by their effect on water relaxation times, which avoids the delay of culture. Quantum dots, semiconductor nanocrystals with narrow, size-tunable emission, became standard in research imaging and multiplexed assays but have made little clinical progress, partly because the brightest formulations c","c":["nanomedicine"],"k":"technology","x":"emerging","h":"present","w":1416,"e":"Tumour genotyping from blood is routine care, and a randomized trial used circulating tumour DNA to guide chemotherapy in stage II colon cancer; no multi-cancer blood test has been shown to reduce mortality in people.","a":"Lateral flow tests and tumour genotyping are routine clinical care; a cell-free DNA colorectal screen was approved in the United States in 2024, and multi-cancer tests are sold outside organised screening programmes rather than reimbursed by them.","r":"reversible","n":7},{"s":"natasha-vita-more","t":"Natasha Vita-More","d":"American designer and theorist who wrote the Transhumanist Arts Statement, designed the Primo Posthuman body concept, and led Humanity+ for much of the 2010s.","g":["transhumanism","design","cryonics","human enhancement","art"],"b":"Natasha Vita-More is an American designer, artist and theorist who has worked since the early 1980s on the aesthetics and embodiment of Transhumanism: what an enhanced human body would actually look like, and how a person would relate to it. She authored the Transhumanist Arts Statement, designed the speculative whole-body concept Primo Posthuman, and served as chair and then executive director of Humanity plus. She is one of the few figures in the movement to approach enhancement as a design problem rather than an engineering or philosophical one. Career Vita-More came to futurism through art and media rather than science. In the early 1980s she produced video work on life extension and hosted a cable television programme in Los Angeles covering emerging technology, aging research and futurist thought, at a time when these topics had almost no mainstream outlet. She circulated the Transhumanist Arts Statement in 1982. It framed artistic practice as a way of imagining and prototyping future forms of embodiment, rather than representing existing ones. She took a doctorate at the University of Plymouth in 2012 through its planetary collegium programme, and has taught at the University of Advancing Technology in Arizona. With Max more, to whom she is married, she co-edited The Transhumanist Reader (2013), which remains the standard anthology of the movement's primary texts. Primo ","c":["people"],"k":"person","x":"established","h":"present","w":1040,"n":5},{"s":"negligible-senescence","t":"Negligible senescence","d":"The condition of organisms whose risk of death does not measurably rise, and whose physiological function does not measurably decline, with age after maturity.","g":["aging","comparative biology","mortality","naked mole-rat","hydra","biogerontology"],"b":"Negligible senescence describes organisms in which the risk of death does not measurably increase with age after maturity, and in which reproductive output and physiological function show no age-related decline. The biogerontologist Caleb Finch introduced the concept in his 1990 book Longevity, Senescence, and the Genome. It is a statistical claim about mortality curves, and it does not mean immortality. Animals with negligible senescence still die from predation, disease, injury and starvation, and their populations still turn over. What the term means Most animals follow something close to a Gompertz curve, in which the hazard of death rises roughly exponentially with age. Negligible senescence is the case where the slope of that curve cannot be distinguished from zero. Mortality becomes independent of age: an individual's chance of dying next year is the same at ten as at a hundred, and survivorship declines exponentially rather than sigmoidally. Finch and Steven Austad set out minimal criteria in 2001. A species qualifies if it shows no observable increase in age-specific mortality or decrease in reproduction after sexual maturity, and no observable age-related decline in physiological capacity or disease resistance. Each criterion is a statement about what has been observed, so its strength depends on how large the studied cohort was and how long it was followed. Terminolo","c":["longevity"],"k":"concept","x":"established","h":"present","w":2367,"n":20},{"s":"neural-correlates-of-consciousness","t":"Neural correlates of consciousness","d":"The minimal neural activity jointly sufficient for a specific conscious experience, and the experimental programme that tries to identify it.","g":["consciousness","neuroscience","integrated information","global workspace","anaesthesia","experiment"],"b":"Neural correlates of consciousness (NCC) are the neural events minimally sufficient for a particular conscious experience. The concept was proposed as a deliberately modest research programme: rather than solving the question of why physical processes give rise to experience at all, find out which processes reliably accompany which experiences, and let the mechanism constrain the theory. Francis Crick and Christof Koch put the programme on the agenda in 1990, proposing synchronized gamma-band activity as a first candidate. Three and a half decades later the field has robust experimental paradigms, several well-specified theories, and no consensus on which is right. Defining an NCC David Chalmers's standard formulation distinguishes the content NCC (the minimal neural system whose state determines what a person is conscious of) from the background or state NCC, the conditions of arousal that make consciousness possible at all. Brainstem structures that regulate wakefulness are part of the second but plainly not the seat of visual experience. Two qualifiers do real work. \"Minimal\" excludes the whole brain, which is trivially sufficient. \"Sufficient\" is weaker than \"identical to\": a correlate can be a reliable accompaniment without being the thing itself, which is why NCC results do not by themselves settle whether a machine or an organoid is conscious. A further complication is t","c":["minds"],"k":"concept","x":"emerging","h":"present","w":1428,"n":14},{"s":"neural-decoding","t":"Neural decoding","d":"The inference of a stimulus, intention, or mental state from measured neural activity, and the statistical machinery that makes brain-computer interfaces work.","g":["bci","neural decoding","machine learning","fmri","neural manifolds","mental privacy"],"b":"Neural decoding is the inference of something outside the brain, such as a stimulus, a movement, a word or a state, from measurements of activity inside it. It is the statistical half of every Brain computer interface, and the half where most recent progress has come from. Decoding is formally the inverse of encoding. Encoding asks how a neuron or population responds to a given input; decoding asks what input or intention best explains an observed response. The word \"decoding\" suggests a fixed cipher waiting to be broken, and the picture misleads. In practice a decoder is a model fitted to one person's brain, on one day, for one task, and its performance degrades as any of those conditions changes. Decoding recovers only what varied systematically in the data it was trained on. Origins Motor decoding began with the observation that neurons in primary motor cortex are broadly tuned to the direction of arm movement, each firing most for a preferred direction and less for others. No single cell specifies direction, but a weighted vector sum across a population does. This population vector was described in the mid-1980s. The result showed that a continuous variable could be extracted from spike counts, and it set up the population-level framing the field still uses. Sensory decoding developed in parallel in human neuroimaging. Pattern-classification methods applied to functional MR","c":["cybernetics","minds"],"k":"concept","x":"established","h":"present","w":1314,"n":31},{"s":"neural-dust","t":"Neural dust and ultrasonic implants","d":"A proposed class of millimetre-scale wireless implants powered and read out by ultrasound, intended to replace tethered electrode arrays with distributed untethered sensors.","g":["implants","ultrasound","wireless","miniaturization","bci","neural recording"],"b":"Neural dust and ultrasonic implants are miniature, battery-free devices that draw their power from an external ultrasound beam and report their measurements by modulating the sound they reflect back. The concept was proposed in 2013 to get around the central failure mode of implanted recording, which lies in the wires, connectors and skull penetrations that tether the electrode to the outside world rather than in the electrode itself. Despite the name, the demonstrated devices are millimetre-scale, not nanoscale, and the published in vivo work is confined to peripheral nerve and muscle in rodents. The problem it addresses Chronic neural recording fails at its interfaces. Penetrating arrays such as the Utah array lose channels over months to years as tissue encapsulates the shanks, but the more mundane failures are mechanical. A rigid array tethered to a skull-mounted connector transmits every micromotion of the brain into the tissue, insulation on the wire bundle delaminates, and a percutaneous pedestal is a permanent infection route. Raising the channel count makes all of this worse, because more channels mean more wires through the same skull opening. The neural dust proposal inverts the architecture. In place of one large array with many wires, it distributes many independent, sealed, wireless motes, each recording locally and each small enough that the tissue response aroun","c":["cybernetics","nanomedicine"],"k":"technology","x":"experimental","h":"2030s","w":1314,"e":"No human study of ultrasonic neural dust has been published; the in vivo work is in anaesthetized rats and covers peripheral nerve and muscle, not cortex, while related magnetoelectric stimulators have reached first-in-human study.","a":"Nothing to obtain: these are laboratory devices with no approved product, no commercial supplier, and no trial of an ultrasonic mote in a person.","r":"difficult","n":5},{"s":"neuralink","t":"Neuralink","d":"American neurotechnology company founded in 2016 developing a wireless implanted brain-computer interface with flexible electrode threads inserted by a surgical robot.","g":["bci","neurotechnology","implants","elon musk","clinical trials","paralysis"],"b":"Neuralink is a privately held American company developing an implanted Brain computer interface consisting of a coin-sized wireless processor and a set of thin polymer threads carrying electrodes, inserted into cortex by a purpose-built surgical robot. It was founded in 2016 by a group including Elon Musk, who has been its public face and principal funder. The company began implanting the device in humans in January 2024 under an FDA investigational device exemption, and in January 2026 it said 21 people were enrolled in its trials worldwide. As of October 2026 its devices remain investigational and unapproved by any regulator. Neuralink's technical contribution lies largely in engineering and surgery rather than neuroscience: flexible electrode threads that move with the brain, automated insertion, high channel counts in a sealed wireless package, and a hermetic implant with no percutaneous connector. Its scientific results to date have been communicated mainly through livestreams, company blog posts and social media rather than peer-reviewed publication, the criticism academic BCI researchers most often level at it. Technology The N1 implant houses a battery, wireless radio, and signal-processing electronics in a package that sits in a recess milled into the skull, flush with the surrounding bone. From it extend 64 polymer threads bearing 16 electrodes each, 1,024 electrodes ","c":["organizations","cybernetics"],"k":"organization","x":"emerging","h":"late 2020s","w":2503,"n":16},{"s":"neuroprosthetics","t":"Neuroprosthetics","d":"The engineering field that builds devices interfacing directly with the nervous system to restore lost sensory, motor, cognitive, or autonomic function.","g":["neurotechnology","implants","sensory restoration","paralysis","neuromodulation","assistive technology"],"b":"Neuroprosthetics is the engineering discipline concerned with devices that exchange signals directly with the nervous system in order to replace a function the nervous system has lost. It spans devices in routine clinical use, such as the Cochlear implant, the spinal cord stimulator and Deep brain stimulation, as well as devices that exist only in single-patient research studies, such as cortical arrays that restore a sense of touch. The problem that unites them is the interface rather than the electronics: how to place a durable transducer against excitable tissue that reacts to its presence, and how to encode information in a form neurons will accept. Scope and taxonomy Four families are usually distinguished, though real devices increasingly cross the boundaries. Sensory prostheses convert an external stimulus into neural activity. The cochlear implant and the Retinal implant are the archetypes, and vestibular implants for bilateral vestibular loss have reached small human trials. These devices have to solve an encoding problem, because electrodes cannot reproduce the natural code of the sense organ. Motor prostheses read intent and act on it. Cortical systems for people with paralysis fall under Brain computer interface, and peripheral systems that read muscle activity fall under Myoelectric prosthetics. Functional electrical stimulation drives the user's own paralysed musc","c":["cybernetics","bodies"],"k":"technology","x":"emerging","h":"present","w":1467,"e":"Cochlear implants, deep brain stimulators and spinal cord stimulators are in routine clinical use in large patient populations; every bidirectional cortical result rests on single-digit numbers of participants.","a":"Hearing, movement-disorder, pain and bladder devices are approved and reimbursed in high-income countries; cortical, spinal and sensory-feedback systems are available only inside research studies.","r":"difficult","n":27},{"s":"neurorights","t":"Neurorights","d":"A proposed set of human rights covering mental privacy, cognitive liberty, and mental integrity, drafted in response to brain-recording and brain-stimulation technology.","g":["law","human rights","privacy","neurotechnology","governance","regulation"],"b":"Neurorights are a proposed category of human rights protecting the brain and mental life against interference by neurotechnology, covering at minimum the privacy of neural data, freedom from unconsented modification of mental states, and control over one's own cognition. The concept was formulated in 2017 and has moved into law faster than almost any other proposal in technology governance: a constitutional amendment followed within four years, state statutes within seven, and an international recommendation within eight. All of this has happened largely before the technology it anticipates exists in deployable form. The proposed rights Two overlapping formulations are in circulation. Marcello Ienca and Roberto Andorno proposed four: cognitive liberty, the right to use or refuse neurotechnology; mental privacy, protection of neural information; mental integrity, freedom from unauthorised alteration of neural computation; and psychological continuity, protection of the sense of self against unconsented change. The NeuroRights Foundation, founded by the Columbia neuroscientist Rafael Yuste out of the group that published a 2017 set of ethical priorities for neurotechnology in Nature, advocates five: mental privacy, personal identity, free will, fair access to mental augmentation, and protection from algorithmic bias. The fourth restates the Human enhancement question as an entitl","c":["society","cybernetics"],"k":"concept","x":"emerging","h":"present","w":1374,"n":25},{"s":"newlimit","t":"NewLimit","d":"A biotechnology company founded in 2021 to screen transcription-factor combinations that restore youthful function to aged cells without changing their identity.","g":["reprogramming","transcription factors","epigenetics","biotech","aging","liver"],"b":"NewLimit is a biotechnology company founded in 2021 by Brian Armstrong and Blake Byers to develop epigenetic reprogramming into a therapy, using large-scale screens of transcription-factor combinations to find sets that restore youthful function in aged cells without converting them to a different cell type. It is smaller than Altos labs and unusual among longevity companies in publishing negative and intermediate results as it goes. Overview The company's technical bet is that the canonical Yamanaka factors are a poor tool for rejuvenation. Takahashi and Yamanaka selected the four-factor set for its ability to drive cells all the way to pluripotency, which is precisely the property that makes it dangerous in a living animal, where cells that lose identity form teratomas. NewLimit's premise is that the space of transcription factors contains combinations that produce the rejuvenation without the dedifferentiation, and that finding them is a search problem rather than a mechanism problem. That framing shapes the company. Most of its investment goes into the screening platform: delivering combinatorial sets of factors into primary human cells, measuring the result with single-cell transcriptomics and functional assays, and using the data to select the next round. History Armstrong, the chief executive of the cryptocurrency exchange Coinbase, and Byers, a venture investor with a b","c":["organizations","longevity"],"k":"organization","x":"emerging","h":"2030s","w":1104,"n":11},{"s":"nick-bostrom","t":"Nick Bostrom","d":"Swedish philosopher who defined existential risk as a field, wrote Superintelligence, and formulated the simulation argument and the vulnerable world hypothesis.","g":["existential risk","transhumanism","artificial intelligence","philosophy","forecasting"],"b":"Nick Bostrom is a Swedish philosopher whose work established existential risk as a research programme and whose 2014 book Superintelligence moved the risk from advanced artificial intelligence into mainstream policy discussion. He founded and directed the Future of Humanity Institute at Oxford from 2005 until its closure in 2024, and he is one of the small number of academic philosophers who have taken transhumanist claims seriously enough to argue for them in peer-reviewed venues. Career Bostrom studied physics, computational neuroscience and philosophy across four institutions before taking a doctorate at the London School of Economics in 2000 on anthropic reasoning, the problem of what an observer may infer from the fact of their own existence. That thesis became Anthropic Bias (2002), and its observation-selection machinery recurs throughout his later work. In 1998 he co-founded the World Transhumanist Association with the philosopher David Pearce; the organization later became Humanity plus. In 2005 he founded the Future of Humanity Institute within Oxford's Faculty of Philosophy. It brought together an unusual group of philosophers, mathematicians and computer scientists, among them Anders sandberg, Toby Ord and, later, Eric drexler. For nearly two decades FHI produced work on Whole brain emulation, global catastrophic risk, Human enhancement and AI alignment. It closed i","c":["people","society"],"k":"person","x":"established","h":"present","w":1000,"n":29},{"s":"nir-barzilai","t":"Nir Barzilai","d":"Israeli-American physician-scientist whose centenarian genetics work and proposed TAME trial aim to make aging itself an acceptable regulatory indication.","g":["aging","centenarians","genetics","metformin","clinical trials","geroscience","regulation"],"b":"Nir Barzilai is an Israeli-American physician-scientist at the Albert Einstein College of Medicine in New York, where he directs the Institute for Aging Research and leads a long-running study of exceptionally long-lived Ashkenazi Jewish families. He is best known as the principal designer of TAME, a proposed trial of Metformin whose endpoint was constructed to force a regulator to treat aging as something a drug can be approved to address. As of 2026 TAME had not been funded at the scale it requires, had not enrolled, and had reported no results. Overview Barzilai's two bodies of work rest on different kinds of evidence. One is observational human genetics: a cohort of centenarians and their children, assembled to ask which inherited variants separate people who reach extreme age from people who do not. The other is regulatory strategy: an argument that the Geroscience hypothesis cannot be tested until an endpoint exists that a health authority will accept for a drug aimed at aging rather than at a named disease. The genetics is descriptive and largely uncontested. The trial built to settle the second question has never been funded at the scale it requires. Career Barzilai took his MD at the Technion in Haifa and trained in internal medicine and endocrinology before joining the faculty of the Albert Einstein College of Medicine in the Bronx. His early laboratory work concerned","c":["people","longevity"],"k":"person","x":"established","h":"present","w":1612,"n":16},{"s":"non-invasive-neuromodulation","t":"Non-invasive neuromodulation","d":"Magnetic, electrical, and ultrasonic techniques that alter neural excitability through the intact skull or peripheral nerves, without surgery or implanted hardware.","g":["tms","tdcs","ultrasound","vagus nerve","cognitive enhancement","replication"],"b":"Non-invasive neuromodulation covers the techniques that change nervous-system activity from outside the body: magnetic pulses that induce currents in cortex, weak direct or alternating currents applied to the scalp, focused ultrasound aimed through the skull, and electrical stimulation of peripheral nerves reachable at the skin. These methods avoid the surgery, cost, and hardware dependence of Deep brain stimulation and of the implanted devices grouped under Neuroprosthetics, whose stimulation can be adjusted or switched off but whose electrodes come out only with another operation. The price is far less spatial precision and shallower reach, and several of the most popular methods rest on an evidence base that has not survived rigorous replication. Modalities Transcranial magnetic stimulation (TMS) discharges a capacitor through a coil held against the scalp, producing a rapidly changing magnetic field that induces an electric field in the underlying cortex strong enough to depolarize axons. A single pulse over motor cortex produces a measurable twitch. That gives TMS something no other non-invasive method has: a direct, objective readout that the stimulation reached its target, a form of ground truth that recording-based systems such as a Brain computer interface have to establish statistically. The therapeutic form is repetitive TMS delivered in trains over days, and pattern","c":["cybernetics","enhancement"],"k":"technology","x":"emerging","h":"present","w":1742,"e":"Repetitive TMS for depression is supported by sham-controlled trials in patients and is cleared and reimbursed; tDCS enhancement studies in healthy adults are small and showed no reliable effect when pooled.","a":"TMS is delivered in clinics and covered by many health systems; tDCS has no approved US indication yet is sold as a consumer wellness device and built at home; ultrasound is research-only.","r":"reversible","n":27},{"s":"nootropics","t":"Nootropics","d":"Substances taken to improve cognition in healthy people, a category whose best-evidenced members produce small effects and whose best-selling members produce none.","g":["cognition","enhancement","pharmacology","supplements","evidence","regulation"],"b":"Nootropics are substances taken with the intention of improving memory, attention, motivation or executive function in people who are not cognitively impaired. The category is defined by user intent rather than by pharmacology, and it spans prescription stimulants, an over-the-counter supplement industry, and compounds sold as research chemicals. The evidence divides sharply: a few agents produce small, replicable effects on laboratory tasks, and most of the market produces none. Origins and definition The Romanian pharmacologist Corneliu Giurgea synthesised piracetam at the Belgian firm UCB in 1964 and coined \"nootropic\" (from the Greek for mind-turning) around 1972 to name a class of drug he believed acted on higher integrative brain function without the sedation, stimulation or toxicity of existing psychoactive agents. He proposed five criteria: enhancement of learning and memory; protection of learned behaviour against disruption; protection of the brain against physical or chemical injury; improvement of tonic cortical control mechanisms; and an absence of the usual psychotropic side effects. The criteria have not aged well as a research programme. No compound has been shown to meet all five in humans, and piracetam itself, the drug the definition was built around, has never been approved in the United States and has weak evidence for the indications it is licensed for els","c":["enhancement"],"k":"intervention","x":"contested","h":"present","w":1486,"e":"Meta-analyses in healthy adults find small effects of stimulants and modafinil on laboratory tasks; no trial has shown any nootropic improves a real-world outcome, and the racetams have almost no modern human data.","a":"Caffeine and supplement blends are sold over the counter with no efficacy review; stimulants and modafinil are prescription-only and used off-label; racetams are bought online outside any approval.","r":"reversible","n":19},{"s":"crispr-off-target-effects","t":"Off-target effects in genome editing","d":"Unintended DNA changes caused by genome editors, either at sites resembling the target or at the target itself, and the assays used to find them.","g":["crispr","genome editing","safety","gene therapy","regulation","mutagenesis"],"b":"Off-target effects in genome editing are DNA changes that an editor makes where it was not intended to act. In practice the term has widened to cover a second and arguably more consequential category: unintended outcomes at the correct site, where the editor cut exactly where instructed and the cell's repair produced something other than the desired edit. Off-target cutting was reported within a year of Crispr cas9 being adapted to human cells. The on-target failure modes took most of the following decade to characterise, and both classes have absorbed a substantial share of the field's effort since. What counts as an off-target effect Guide RNAs tolerate mismatches, particularly at positions distant from the PAM, so a twenty-nucleotide spacer typically has dozens to hundreds of partially matching sites in a mammalian genome. Whether any of them is actually cut depends on chromatin accessibility, the concentration and persistence of the editor, and the specific mismatch pattern. Cutting at such a site produces the same indels as an on-target cut, in a gene nobody chose. Editors that do not cut have their own version of the problem. Base editors carry a deaminase that can act on transiently exposed single-stranded DNA anywhere in the genome, entirely independently of where the guide RNA directs the protein. That mechanism leaves scattered single-base changes with no cut site to ","c":["genetics","society"],"k":"concept","x":"established","h":"present","w":1192,"n":26},{"s":"optogenetics","t":"Optogenetics","d":"A technique that makes selected neurons light-sensitive by expressing microbial opsin genes in them, allowing their activity to be switched on or off on a millisecond timescale.","g":["neuroscience","opsins","gene delivery","circuit mapping","vision restoration","research tools"],"b":"Optogenetics is the use of light-sensitive proteins, introduced into cells by gene transfer, to control the electrical activity of those cells with light. In neuroscience it made possible a specific experiment that had not been available before: activating or silencing one genetically defined population of neurons, in a behaving animal, on the timescale of a single action potential, while leaving neighbouring cells untouched. Electrical methods such as Deep brain stimulation cannot provide that combination of cell-type specificity and millisecond timing. How it works The active ingredient is a microbial opsin, a membrane protein from algae, archaea or bacteria that absorbs light and moves ions across the membrane. Channelrhodopsin-2, from the green alga Chlamydomonas reinhardtii, opens a cation channel when illuminated with blue light, depolarizing the cell. Halorhodopsin, a chloride pump from a haloarchaeon, and archaerhodopsin, a proton pump, hyperpolarize the cell under yellow or green light and so silence it. All of them require the cofactor all-trans retinal. Vertebrate brain tissue happens to supply it in sufficient quantity, and without that biological accident the technique would not work in mammals. An experiment has three parts. First the opsin gene is delivered to the target cells, usually by Aav vectors carrying a cell-type-specific promoter, or by crossing a transg","c":["cybernetics","genetics"],"k":"technology","x":"experimental","h":"2030s","w":1336,"e":"One published case report describes partial visual recovery in a patient with retinitis pigmentosa after opsin delivery to retinal ganglion cells; every use outside the eye, from engram control to cochlear and cardiac work, is in animals.","a":"Nothing to obtain clinically: no optogenetic therapy is approved anywhere and the only human use is inside ophthalmology trials, while opsin constructs are standard laboratory reagents.","r":"irreversible","n":16},{"s":"organ-bioprinting","t":"Organ bioprinting","d":"The additive manufacture of living tissue by depositing cells and biomaterials in a programmed pattern, pursued as a route to transplantable organs but limited so far to simple structures.","g":["bioprinting","tissue engineering","vascularization","regenerative medicine","transplantation","biofabrication"],"b":"Organ bioprinting is the additive manufacture of living tissue: a machine deposits cells, hydrogels and sacrificial support materials in a programmed three-dimensional pattern, and the construct is then cultured until the cells remodel it into something with tissue-like structure and function. The technique borrows its motion control from industrial 3D printing and its biology from Tissue engineering. In the laboratory it has produced skin, cartilage, corneal stroma, vascular grafts and beating cardiac patches. It has not produced a solid organ that anyone has transplanted into a person, and most of what follows concerns why. How it works A bioprinter converts a digital model, usually derived from a patient's CT or MRI scan, into a toolpath and then lays down material along it. Three families of deposition method dominate. Extrusion printing pushes a viscous cell-laden gel through a nozzle by pneumatic pressure or a screw. It is the workhorse of the field: cheap, tolerant of high cell densities, and compatible with most hydrogels. Its weaknesses are resolution, typically a few hundred micrometres, and shear stress at the nozzle, which damages cells. Extrusion also cannot print an unsupported soft gel, because a low-stiffness ink collapses under its own weight. The standard answer is embedded printing, in which the nozzle deposits into a supporting bath of granular gel that beha","c":["bodies"],"k":"technology","x":"experimental","h":"2040s","w":1791,"e":"A printed autologous ear cartilage implant has been placed in patients in a microtia trial and printed skin has reached early human work; no printed solid organ has been implanted in a person or supported an animal.","a":"Nothing to obtain: printed tissue is sold only as a research and drug-screening product, and the sole human implants are inside small company-run trials.","r":"difficult","n":14},{"s":"organ-shortage","t":"Organ shortage","d":"The persistent gap between the number of people who need a transplant and the number of usable donated organs, which drives most work on engineered and animal-derived replacements.","g":["transplantation","health policy","donation","allocation","bioethics","kidney"],"b":"Organ shortage is the structural gap between the number of people who would benefit from a transplant and the number of organs available to transplant. It is the practical reason most of the technologies covered elsewhere on this wiki exist: Xenotransplantation, Organ bioprinting, Lab grown organs and mechanical support such as the Artificial heart are all responses to a supply constraint that donation policy has narrowed but never closed. The shortage is usually described with waiting-list statistics, which understate it, because being on a list requires being sick enough to need an organ and well enough to survive receiving one. The arithmetic More than a hundred thousand people are registered on the United States transplant waiting list at any time, the large majority of them waiting for a kidney, and federal agencies put the number dying each day while listed at around seventeen. The United States performed a record of more than forty-six thousand transplants in 2023 and volumes have continued to rise since, and yet the list has not shortened, because listing rates rise with capacity. The list is a poor measure of need. In the United States more than half a million people are on dialysis, several times the number registered for a kidney; the rest are excluded by age, comorbidity, insurance status, or a referral that never happened. For livers, hearts and lungs the equivalen","c":["bodies","society"],"k":"concept","x":"established","h":"present","w":1545,"n":19},{"s":"organoids","t":"Organoids","d":"Self-organizing tissue cultures grown from stem cells that reproduce some of the architecture and function of an organ, used mainly for disease modelling rather than transplantation.","g":["stem cells","disease modelling","brain organoids","drug screening","regenerative medicine","bioethics"],"b":"Organoids are three-dimensional cell cultures, grown from stem cells, that self-organize into structures reproducing some of the cell types, spatial arrangement and function of a real organ. They are not miniature organs. A cerebral organoid has cortical layers and firing neurons but no blood supply, no immune cells, no thalamic input and no consistent body plan; an intestinal organoid has crypts and absorptive cells but no nerves and no microbiome. Their value is that they are human, three-dimensional, and can be generated in numbers large enough to screen against. How they are made Two derivation routes dominate. The adult-stem-cell route takes tissue-resident stem cells, from an intestinal biopsy for example, and embeds them in a laminin-rich basement membrane gel with a defined cocktail of niche factors, typically including R-spondin, epidermal growth factor, and inhibitors of BMP and TGF-β signalling. The cells proliferate and spontaneously build crypt-villus architecture. These organoids are epithelial only, genetically stable, and can be passaged for years. The pluripotent route starts from embryonic stem cells or from Induced pluripotent stem cells generated with the Yamanaka factors, and applies a timed sequence of differentiation cues that mimics embryonic patterning: germ-layer induction, then regional specification, then self-organization. This route produces organo","c":["bodies"],"k":"technology","x":"emerging","h":"present","w":1307,"e":"Organoids grown from a patient's own biopsy are used in the Netherlands to predict that patient's response to cystic fibrosis drugs; organoid-derived cells have been transplanted only in early trials, and no organoid has replaced an organ.","a":"A laboratory product rather than a treatment: the culture reagents are sold commercially, and the only patient-facing uses are the Dutch cystic fibrosis drug-response assay and a few early transplantation trials.","r":"difficult","n":22},{"s":"osseointegration","t":"Osseointegration","d":"The direct structural fusion of living bone to a titanium implant, the biological principle underlying dental implants and skeletally anchored limb prostheses.","g":["prosthetics","implants","titanium","amputation","bone","biomaterials"],"b":"Osseointegration is the formation of a direct, load-bearing connection between living bone and the surface of an implanted material, without intervening fibrous tissue. It is the reason a dental implant can carry chewing forces for decades, and it is the enabling principle for prostheses anchored to the skeleton rather than strapped to it. The phenomenon was found by accident, in an experiment about blood flow, and its extension from teeth to limbs took a further quarter of a century. How it works Bone ordinarily walls off foreign material with a fibrous capsule, which under load becomes a loosening interface. Titanium behaves differently. A spontaneous, self-repairing oxide layer a few nanometres thick forms on its surface, adsorbs proteins in a configuration osteoblasts can attach to, and provokes little inflammatory response. Bone then forms directly against the oxide. Two processes contribute. In distance osteogenesis, new bone grows from the existing surface toward the implant; in contact osteogenesis, osteogenic cells migrate onto the implant surface and lay down matrix outward from it. Surface topography strongly influences which dominates, which is why modern implants are roughened by grit-blasting, acid-etching, or anodizing rather than left machined smooth. Fixation has two phases that are often confused. Primary stability is mechanical: the press-fit or screw-thread ","c":["bodies"],"k":"technology","x":"established","h":"present","w":1194,"e":"Dental implants have decades of routine clinical use in millions of patients; bone-anchored limbs rest on uncontrolled patient series reporting longer prosthesis wear time and better mobility, not on randomized trials.","a":"Dental implants are a routine commercial procedure worldwide; bone-anchored limbs are performed at a small number of specialist centres, and the US screw-fixated system entered under a humanitarian exemption that caps volume.","r":"difficult","n":7},{"s":"overpopulation-and-longevity","t":"Overpopulation and life extension","d":"The objection that extending human lifespan would cause unsustainable population growth, and the demographic modelling that finds the effect smaller than assumed.","g":["demography","aging","fertility","workforce","resources","policy","ethics"],"b":"Overpopulation and life extension concerns the most frequently raised objection to radical longevity research: that if people stopped dying of age-related causes, population would grow beyond what the planet can support. The objection is intuitive, though the same arithmetic would apply to curing any specific disease of old age. Demographers who have examined it conclude that the effect is real but far smaller than the intuition suggests, because births drive population dynamics far more than deaths at old ages do. In low-fertility countries the argument now also runs the other way, with some advocates presenting longer healthy lives as a remedy for shrinking workforces, a claim the labour-economics evidence supports only in part. The arithmetic A population's growth rate depends on how many children are born and how many survive to have children of their own. Deaths after the end of the reproductive span remove people from the population without affecting the number of descendants they produce. Eliminating mortality at seventy therefore adds to the stock of living people without altering the reproductive dynamics at all. What changes is the shape of growth, not its rate. Under a regime with constant births and no deaths, population grows linearly, adding roughly the same number each year, instead of exponentially, as compounding reproduction does. Linear growth over a century ","c":["society","longevity"],"k":"concept","x":"contested","h":"2050s+","w":2388,"n":5},{"s":"pantropy","t":"Pantropy","d":"The proposal to engineer humans to suit other worlds rather than engineering those worlds to suit humans, and the ethical problems of designing offspring for an environment.","g":["space settlement","germline","adaptation","terraforming","science fiction","ethics"],"b":"Pantropy is the proposal to modify humans so that they can live on other worlds without extensive artificial habitats, in contrast to terraforming, which modifies the world to suit unmodified humans. The word was coined by the science fiction writer James Blish, whose The Seedling Stars stories imagined \"adapted men\" engineered for environments as hostile as the surface of Ganymede and as small as a freshwater puddle. No research programme pursues it. As a framing device it recurs throughout discussions of Mars settlement, where it amounts to heritable genome editing with a destination attached. Origins The idea predates the word. In 1929, J.D. Bernal argued in The World, the Flesh and the Devil that humans would eventually rebuild their own bodies to suit conditions off Earth, treating the biological form as an engineering constraint rather than a given. Three decades later, Manfred Clynes and Nathan Kline coined the term \"cyborg\" for this purpose: their 1960 paper proposed augmenting human physiology so that astronauts could function in space without carrying a terrestrial environment with them. The word now attached to neural implants began as a space-medicine proposal, which is one measure of how closely the two literatures run. Blish supplied the term and the contrast. Writing in the same decade that Jack Williamson's coinage of \"terraforming\" entered circulation, he set t","c":["space","enhancement"],"k":"concept","x":"speculative","h":"2050s+","w":1323,"n":7},{"s":"parabiosis-and-young-blood","t":"Parabiosis and young blood","d":"Experiments joining the circulation of young and old animals, and the attempts to translate their rejuvenating effects into plasma-based treatments for humans.","g":["parabiosis","plasma","aging","gdf11","rejuvenation","clinical trials"],"b":"Parabiosis and young blood refers to a line of experiments in which the circulatory systems of a young and an old animal are joined, and to the effort to extract from those experiments a treatment that can be given to people. In mice, heterochronic parabiosis improves tissue repair, neurogenesis and several molecular measures of age in the older partner, one of the more striking results in biogerontology. Translation has been troubled. The best-known candidate factor is disputed, an alternative interpretation attributes the effect to dilution instead of anything youthful, and the human market ran far ahead of the science. The experiments In surgical parabiosis, two animals are joined along a flank incision so that a shared vasculature develops. The technique dates to Paul Bert's rat experiments in 1864 and was used through the twentieth century to study endocrine and metabolic signals. Mid-century work reported that old rats joined to young partners survived longer than unjoined controls, in studies with small numbers and considerable surgical mortality. The modern field begins in 2005, when Conboy and colleagues showed that exposing an old mouse to a young circulation restored the activation of muscle satellite cells and liver progenitors, largely by recovering Notch signalling. The aged cells themselves were not irreversibly damaged; they were responding to their environment.","c":["longevity"],"k":"intervention","x":"experimental","h":"2030s","w":1343,"e":"Human work is limited to small plasma-infusion and plasma-exchange studies reporting feasibility, biomarker shifts, and one debated subgroup result; every rejuvenation and lifespan finding is from mice.","a":"Not approved for aging anywhere; plasma products are licensed only for medical indications, and clinics in loosely regulated jurisdictions sell young-donor infusions of the kind the FDA warned against in 2019.","r":"reversible","n":11},{"s":"partial-reprogramming","t":"Partial reprogramming","d":"Transient expression of pluripotency factors that resets age-associated epigenetic marks in a cell while stopping short of erasing its differentiated identity.","g":["reprogramming","rejuvenation","epigenetics","aging","gene therapy"],"b":"Partial reprogramming is the deliberate interruption of the reprogramming process partway through, so that a cell sheds age-associated epigenetic marks without becoming a stem cell. It is possible because two things happen at different speeds when pluripotency factors are switched on: the epigenome starts changing almost immediately, while the cell's committed identity survives for considerably longer. The whole technique is built around exploiting that gap. The reprogramming trajectory When the Yamanaka factors are expressed in a fibroblast, the cell enters a process that ends, in a small minority of cases, at pluripotency. The process has recognisable stages. An early phase involves loss of the somatic transcriptional programme and, in fibroblasts, a mesenchymal-to-epithelial transition. A maturation phase follows, in which some cells activate the endogenous pluripotency network. Only then does the cell become an induced pluripotent stem cell and stop depending on the exogenous factors. Methylation age, as read by an Epigenetic clock, falls steadily from the start of this process instead of dropping at the end. Nadia Olova and colleagues mapped the two curves and found that epigenetic age declines well before somatic identity is lost, which established that a usable window exists. Diljeet Gill and colleagues in Wolf Reik's laboratory took human fibroblasts into the maturation","c":["longevity","genetics"],"k":"technology","x":"experimental","h":"2030s","w":1462,"e":"A phase 1 trial of an OSK therapy in optic neuropathies dosed its first participant in June 2026 and reported no results; published human data are in cultured cells, and every in vivo result is in mice.","a":"Not available to patients: no approved product as of 2026, and the only human exposure is a phase 1 safety trial in optic neuropathies that began dosing in June 2026.","r":"context","n":19},{"s":"personal-identity-and-continuity","t":"Personal identity and continuity","d":"The question of what makes a person at one time the same person as at another, and what, if anything, must be preserved for that person to survive.","g":["identity","philosophy of mind","parfit","survival","consciousness","bioethics"],"b":"Personal identity and continuity is the problem of what makes a person existing at one time the same person as one existing at another, and what has to be preserved for that person to survive a change. It is an old question in philosophy that acquires practical force whenever a technology proposes to interrupt, copy, or reconstruct a mind, which is why it recurs across Mind uploading, Cryonics, gradual neural replacement, and advance directives in dementia. Nothing in neuroscience answers it, because the question concerns how to describe what happens, not what happens. The classical positions John Locke separated the person from both the soul and the animal. A person, he wrote, is a thinking intelligent being that can consider itself as itself across time, and personal identity extends only as far as consciousness (in effect, memory) extends backwards. The proposal explains why a person is responsible for past acts they remember and severs identity from bodily persistence. Two objections followed quickly. Joseph Butler charged the account with circularity: to remember doing something is already to remember oneself doing it, so memory presupposes identity rather than constituting it. Thomas Reid's brave officer case sharpened it: an old general remembers being a young officer, the young officer remembered being a flogged schoolboy, but the general remembers nothing of the school","c":["minds","society"],"k":"concept","x":"contested","h":"indefinite","w":1310,"n":26},{"s":"personalized-mrna-cancer-vaccines","t":"Personalized mRNA cancer vaccines","d":"A therapy in which one patient's tumour is sequenced, its mutation-derived antigens are ranked by algorithm, and a synthetic mRNA encoding them is manufactured for that person alone.","g":["cancer","mrna","immunotherapy","neoantigens","melanoma","oncology","vaccines"],"b":"Personalized mRNA cancer vaccines are therapies in which a patient's tumour is sequenced alongside their healthy tissue, the mutations unique to that tumour are ranked by algorithm, and a synthetic messenger RNA encoding the highest-ranked of them is manufactured for that one person. The injected mRNA instructs the recipient's own cells to make and display those mutant protein fragments, on the expectation that T cells will then recognise and kill cells carrying them. The field calls the class individualized neoantigen therapy; in August 2026 one such product reported the first positive phase 3 result. How it works A neoantigen is a protein fragment that exists only because a tumour mutated. It is absent from every healthy cell, which makes it a target the immune system can attack without attacking the patient. The difficulty is that neoantigens are almost entirely private to one tumour, so there is nothing to stock on a shelf. The workflow answers that by manufacturing per patient. A biopsy and a blood sample are sequenced and compared, separating the tumour's mutations from the person's inherited variation. An algorithm then scores those mutations for the chance that a fragment carrying them will be displayed on the cell surface by that patient's own major histocompatibility complex molecules and recognised by a T cell. Moderna's product, intismeran autogene, encodes up to 34","c":["genetics","longevity"],"k":"intervention","x":"experimental","h":"late 2020s","w":1612,"e":"A randomised phase 3 in 1,137 people with resected melanoma met its recurrence-free survival endpoint according to its sponsors, who released no hazard ratios; overall survival is unreported from it and only exploratory in the phase 2b behind it.","a":"Available only inside company-run clinical trials; no individualized neoantigen therapy is approved by any regulator as of August 2026, and no price has been announced.","r":"partly-reversible","n":3},{"s":"polygenic-embryo-screening","t":"Polygenic embryo screening","d":"The ranking of IVF embryos by polygenic risk scores computed from their inferred genotypes, sold commercially since 2019 and rejected as unvalidated by professional genetics bodies.","g":["polygenic scores","ivf","embryo selection","genomics","bioethics","reproduction"],"b":"Polygenic embryo screening, formally preimplantation genetic testing for polygenic conditions (PGT-P), ranks the embryos produced in an IVF cycle by polygenic scores calculated from hundreds of thousands of common genetic variants. Clinics and direct-to-consumer companies use it to report an embryo's relative predicted risk for conditions such as type 2 diabetes, coronary artery disease and schizophrenia, and in some cases for non-disease traits including height and cognitive test performance. The laboratory procedure is a modest extension of routine embryo genotyping; the dispute concerns what the resulting rankings are worth. How it works PGT-P attaches to an existing clinical workflow rather than replacing it. Five or six days after fertilisation, an embryologist biopsies five to ten cells from the trophectoderm, the outer layer of the blastocyst that will become placenta rather than fetus. The DNA in that sample is measured in picograms, so it is first amplified across the whole genome and then read on a SNP array or by low-pass sequencing. The resulting genotype is sparse and noisy. To make a polygenic score usable, the laboratory imputes the missing variants. It genotypes both parents, reconstructs which parental haplotypes each embryo inherited, and fills in the rest by reference to a haplotype panel. An embryo's score is therefore reconstructed rather than measured dire","c":["reproduction","genetics","society"],"k":"technology","x":"contested","h":"present","w":1694,"e":"Children have been born after polygenic ranking of embryos, but no study has followed selected children to test the predicted gain; the scores are validated in adult cohorts, mostly of European ancestry.","a":"Sold in the United States as a laboratory-developed test, an add-on to a self-funded IVF cycle at a small number of clinics; the United Kingdom does not permit it and several European states restrict it.","r":"irreversible","n":19},{"s":"posthuman","t":"Posthuman","d":"A hypothetical being whose central capacities exceed the human maximum, and, in a separate scholarly tradition, a critique of the humanist subject itself.","g":["transhumanism","posthumanism","identity","enhancement","philosophy","critical theory"],"b":"Posthuman names a being whose general capacities exceed the maximum attainable by any current human, to a degree that would put it outside the category \"human\" as that category is currently used. The word carries a second, largely unrelated meaning in the humanities, where posthumanism is a critique of the humanist picture of the self-contained rational subject rather than a forecast about future beings. The two usages share a prefix and almost nothing else, and the resulting confusion is a persistent feature of the literature. Transhuman, posthuman, and the gradient In transhumanist writing the two terms mark positions on a continuum. A transhuman is a person in transition: someone using enhancement technologies but still recognisably a member of the species. A posthuman lies beyond that, past whatever threshold makes the species label stop applying. Fm 2030 introduced the transitional sense in the 1970s, describing transhumans as evolutionary intermediaries identifiable by their reproductive choices, prostheses, mobility and rejection of traditional social forms. The difficulty is that nobody has specified where the threshold sits, and most attempts to place it collapse under examination. A person with a Cochlear implant and a pacemaker who lives to 110 is not posthuman on anyone's account. A brain emulation running at a thousand times biological speed would be on almost ever","c":["foundations","society"],"k":"concept","x":"speculative","h":"indefinite","w":1284,"n":18},{"s":"exoskeleton","t":"Powered exoskeletons","d":"Wearable powered frames that apply force in parallel with the wearer's own limbs, used for gait rehabilitation, industrial load support, and proposed strength augmentation.","g":["robotics","rehabilitation","mobility","wearables","human augmentation","actuators"],"b":"Powered exoskeletons are wearable machines whose structure runs alongside the body's own skeleton and whose actuators apply torques across the wearer's joints. They are used clinically to move the legs of people with paralysis, industrially to offload weight from a worker's back and shoulders, and militarily, mostly in prototype, to carry loads. The engineering problem is deceptively hard, because an exoskeleton must produce more benefit than the metabolic and mechanical cost of carrying it. Unlike the implanted devices grouped under Neuroprosthetics, or the skeletal anchorage described in Osseointegration, an exoskeleton touches the body only at straps and cuffs. That is both its principal safety advantage and the source of most of its engineering difficulty. How they work Three subsystems define a device. The structure transmits load, ideally into the ground rather than into the wearer, and must keep its joints aligned with human joints that are not simple hinges; misalignment produces shear at the attachment points and is a common source of discomfort and abandonment. The actuators supply torque, most often through electric motors with harmonic or ball-screw transmissions, sometimes hydraulically for high force, and sometimes not at all in passive designs that store energy in springs. The controller decides when and how much to assist. Intent detection is the control problem","c":["bodies","enhancement"],"k":"technology","x":"emerging","h":"present","w":1491,"e":"People with spinal cord injury or stroke walk in these devices under supervision, though reviews find the evidence too thin to show an advantage over conventional gait training; the clearest measured gains are metabolic savings in healthy walkers.","a":"Cleared for clinical use and, in the United States since 2014, for personal use; medical devices cost tens of thousands of dollars or more with limited payer coverage, while passive industrial exosuits are sold outright.","r":"reversible","n":17},{"s":"precautionary-principle","t":"Precautionary principle","d":"The regulatory doctrine that scientific uncertainty about a serious or irreversible harm is not by itself a reason to permit the activity that might cause it.","g":["governance","risk","regulation","biotechnology","law","uncertainty"],"b":"The precautionary principle holds that where an activity threatens serious or irreversible harm, the absence of scientific certainty about that harm is not a sufficient reason to allow the activity to proceed unrestricted. It exists in weak versions that merely license regulators to act under uncertainty and strong versions that shift the burden of proof onto whoever proposes the activity. The two versions differ in kind rather than degree, and most arguments about the principle turn out to be arguments about which one is being invoked. Formulations The weak form authorises action; the strong form requires it. A third and stronger reading, sometimes attributed to the principle by its critics and rarely defended in print, would prohibit any activity whose safety cannot be affirmatively demonstrated. That reading is incoherent, since no activity can be shown safe in that sense and inaction has consequences of its own, but it is a straw man of the versions that appear in law. Origins and legal status The German Vorsorgeprinzip (roughly, the principle of taking care in advance) entered environmental legislation in the 1970s as a rationale for acting on forest damage and air pollution before causal chains were established. The idea spread through North Sea protection conferences in the 1980s and reached its most-quoted formulation as Principle 15 of the 1992 Rio Declaration. In Euro","c":["society","foundations"],"k":"concept","x":"contested","h":"present","w":1500,"n":35},{"s":"prime-editing","t":"Prime editing","d":"A genome editing method in which a nicking Cas9 fused to a reverse transcriptase writes a new DNA sequence specified by an extended guide RNA.","g":["crispr","genome editing","gene therapy","reverse transcriptase","biotechnology"],"b":"Prime editing installs a chosen DNA sequence at a chosen site by nicking one strand of the double helix and then writing new bases onto the exposed end from an RNA template carried by the guide itself. Described in 2019, it removes two constraints at once: it needs no double-strand break, and unlike Base editing it is not restricted to particular chemical conversions. Its practical difficulty is the reverse of that generality: the machine is large, the design space for each target is wide, and efficiency varies from excellent to negligible depending on the site. How it works Three things have to happen in order, and each can fail independently: the editor must find and nick the target, the reverse transcriptase must copy the intended sequence onto the exposed strand, and the cell must keep the new sequence rather than discard it. The third step is the one the designer controls least. The pegRNA The editor is a Cas9 nickase, disabled in one of its two nuclease domains so that it cuts only the strand containing the PAM, fused to an engineered reverse transcriptase. The guide is extended into a prime editing guide RNA, or pegRNA, which carries three functional parts: a spacer that specifies the target, a primer binding site complementary to the nicked strand, and a reverse transcription template encoding the desired new sequence. After the nick, the freed 3' end of the DNA anneals","c":["genetics"],"k":"technology","x":"experimental","h":"2030s","w":1358,"e":"Human use is one ex vivo trial in chronic granulomatous disease, which reported restored immune-cell function in a treated patient in 2025; in vivo correction has been shown only in mice.","a":"Not obtainable as a therapy: no prime editing product is approved anywhere as of 2026 and human use is confined to early-phase trials; the reagents are sold for research.","r":"irreversible","n":17},{"s":"procreative-beneficence","t":"Procreative beneficence","d":"Julian Savulescu's principle that prospective parents have moral reason to select, among the children they could have, the one expected to live the best life.","g":["bioethics","reproduction","selection","eugenics","philosophy"],"b":"Procreative beneficence is the principle, stated by Julian savulescu in 2001, that couples who select which of several possible children to bring into existence have significant moral reason to choose the one expected to have the best life, or at least as good a life as the alternatives, on the basis of the relevant information available, including information about traits that are not diseases. It is one of the most cited claims in contemporary reproductive ethics and one of the most widely rejected. Its practical relevance has grown as Embryo selection has moved from testing for single-gene conditions to scoring embryos on statistical predictors of common traits. What the principle says Three features of the principle carry most of its weight, and all three are routinely misread. It is a principle about selection, not modification. It says nothing about Germline editing and applies wherever a choice is made among possible children: which embryo to transfer, which gamete donor to use, and, in a weaker sense, when to conceive. It generates a reason, not an enforceable duty. Savulescu is explicit that the obligation is prima facie and that it does not license coercion, state direction, or the withdrawal of reproductive liberty. On his account a couple who decline to test, or who transfer an embryo with a lower expected wellbeing, act against a reason they have; they do not there","c":["society","reproduction"],"k":"concept","x":"contested","h":"present","w":1390,"n":15},{"s":"progeria","t":"Progeria","d":"A rare fatal childhood disorder caused by one recurrent LMNA mutation, and the standing test case for whether a genetic disease can accelerate aging itself.","g":["aging","rare disease","gene editing","lamin","cardiovascular","biogerontology"],"b":"Progeria, or Hutchinson-Gilford progeria syndrome, is a fatal childhood disease caused by a single recurrent point mutation in LMNA, the gene encoding the nuclear structural proteins lamin A and lamin C. The mutation activates a hidden splice site and produces progerin, a shortened lamin A that stays permanently anchored in the nuclear membrane and distorts the nucleus. Affected children grow poorly, lose hair and subcutaneous fat, develop severe atherosclerosis, and die at an average age of about 14.5 years, more than 80% of them from heart failure or myocardial infarction. Aging research constantly invokes the disease as a natural experiment in accelerated aging, and how far it deserves that role is contested. The mutation Roughly 90% of cases carry the same substitution, c.1824CT, arising fresh in the affected child rather than inherited. The change is silent at the level of the genetic code: it converts one glycine codon into another and alters no amino acid. Instead, it strengthens a cryptic splice donor site inside exon 11, so that a fraction of LMNA transcripts are spliced short. The resulting protein lacks fifty amino acids near its C-terminus. Normal prelamin A is farnesylated, inserted into the inner nuclear membrane, and then cleaved by the protease ZMPSTE24, which removes the farnesylated tail and releases mature lamin A. The fifty-residue deletion takes the cleavag","c":["longevity","genetics"],"k":"concept","x":"established","h":"present","w":1560,"e":"Lonafarnib is the only therapy with human survival data, and it comes from single-arm trials compared against a matched untreated cohort rather than a randomised arm; the base-editing rescue is mouse-only.","n":1},{"s":"proteostasis","t":"Proteostasis collapse","d":"The age-related failure of the chaperone, proteasome and lysosomal systems that keep proteins correctly folded and turned over, and its link to aggregation diseases.","g":["aging","protein folding","chaperones","proteasome","neurodegeneration","mechanisms"],"b":"Proteostasis collapse is the progressive age-related failure of the systems that fold proteins correctly, refold them when they are damaged, and destroy them when they cannot be repaired. Proteostasis, or protein homeostasis, is maintained by a network of several hundred chaperones, the ubiquitin-proteasome system and lysosomal degradation, working under the control of inducible stress responses. Its loss is a primary hallmark in the Hallmarks of aging framework and the mechanistic link between aging and the major neurodegenerative diseases. The proteostasis network A newly made polypeptide must reach one conformation out of an enormous number of possible ones, in a cytoplasm containing several hundred milligrams of protein per millilitre. Molecular chaperones bind exposed hydrophobic surfaces and prevent inappropriate association while folding proceeds; they include the HSP70 and HSP90 families, the small heat-shock proteins, and the chaperonin complex that folds actin and tubulin. Only part of the network does folding work, and the rest handles triage and disposal. Machine-learning models now predict a native structure from sequence well, but that is a different problem from predicting how a chain reaches the structure or how often it fails to, which is what the network exists to manage. Two degradation systems deal with proteins that cannot be rescued. The ubiquitin-proteaso","c":["longevity"],"k":"concept","x":"established","h":"present","w":1208,"n":22},{"s":"psychedelic-therapy","t":"Psychedelic therapy","d":"The administration of serotonergic psychedelics or MDMA alongside psychological support for psychiatric conditions, in trials that cannot be reliably blinded.","g":["psilocybin","mdma","depression","ptsd","clinical trials","blinding","psychiatry"],"b":"Psychedelic therapy is the administration of a psychoactive drug, most often psilocybin or MDMA, in a small number of supervised sessions framed by preparatory meetings and follow-up discussion with trained personnel. What distinguishes it from ordinary psychopharmacology is the claim that one or two sessions, rather than daily medication, can produce durable change in depression, post-traumatic stress disorder, or addiction. Randomized trials in patient populations have reported large short-term effects. Whether those effects belong to the drugs is the question the field has not resolved, because almost everyone involved can tell who received what. How it works Classical psychedelics act as agonists or partial agonists at the serotonin 5-HT2A receptor; in human volunteers, pretreatment with a 5-HT2A antagonist blocks most of the subjective effects, the clearest evidence that the experience depends on this receptor. Neuroimaging during the acute state finds increased diversity of spontaneous cortical signals and reduced segregation between large-scale networks, which has made these drugs a tool in the study of Neural correlates of consciousness apart from any therapeutic use. In rodents and cultured neurons, psychedelics and ketamine promote dendritic spine growth and synapse formation in cortex. Nothing equivalent has been measured in a living human brain. The rationale is tha","c":["minds","enhancement"],"k":"intervention","x":"contested","h":"late 2020s","w":1590,"e":"Randomized trials in human patients report large short-term reductions in depression and PTSD symptoms, but participants and therapists almost always guess the assignment correctly, so drug and expectancy effects remain confounded.","a":"Esketamine is approved for treatment-resistant depression; psilocybin and MDMA remain unapproved medicines, reachable through trials or Australia's authorised-prescriber pathway, and psilocybin is sold at licensed non-medical centres in two US states.","r":"context","n":8},{"s":"quantified-self","t":"Quantified self","d":"A movement and a method for learning about oneself through personal measurement, built on n-of-1 self-experiment and named by two Wired editors in 2007.","g":["self-tracking","measurement","n-of-1","privacy","wearables","citizen science"],"b":"Quantified self is the practice of learning about oneself by measuring oneself, and the name of the movement that formed around that practice after two Wired editors, Gary Wolf and Kevin Kelly, coined the phrase in 2007. Its slogan was \"self-knowledge through numbers\", its characteristic artefact was a talk given at a meetup about a personal experiment, and its intellectual core was the n-of-1 trial. Nearly two decades on, self-tracking is a default feature of consumer devices and the movement that argued for it has largely dissolved. Origins The label arrived at the moment the instruments did. Cheap accelerometers, phones with sensors, and the first consumer activity trackers made it possible to keep a continuous record of sleep, movement, weight or mood without a laboratory. Wolf and Kelly started the Quantified Self blog in 2007; the first show-and-tell meetup followed in 2008, held at Kelly's studio in Pacifica, California, and attended by about thirty people. Wolf's 2010 essay in The New York Times Magazine and a TED talk the same year carried the idea to a general audience. The meetup format did more of the intellectual work than the name suggests. A speaker answered three questions in order: what did you do, how did you do it, and what did you learn. The rule excluded product pitches and forced any presenter to state a method and an outcome, including a null one. Subject","c":["enhancement","society"],"k":"concept","x":"established","h":"present","w":1794,"e":"Self-monitoring raises measured activity in people over the short term; a randomised trial of a workplace wellness programme found more self-reported exercise but no change in clinical measures or spending at 18 months.","a":"Trackers ship in most phones and cost from tens to a few hundred dollars, but much tracking now arrives through an employer or insurer programme rather than a purchase.","r":"context","n":15},{"s":"radiation-hardening-humans","t":"Radiation tolerance in humans","d":"The problem of keeping humans healthy under deep-space radiation, and the shielding, pharmacological, and genetic strategies proposed to raise their tolerance.","g":["radiation","spaceflight","dna repair","shielding","gene editing","cancer risk"],"b":"Radiation tolerance in humans refers to the engineering, pharmacological, and genetic strategies intended to let people survive radiation exposures that current biology handles poorly, principally the charged-particle environment beyond Earth's magnetosphere. It is the constraint that most clearly separates orbital spaceflight from interplanetary travel. Bone and muscle loss are disuse phenomena that respond to exercise; radiation damage accumulates whether or not the crew does anything, and no validated countermeasure exists. The exposure Two components matter, and they pose opposite engineering problems. Galactic cosmic rays are a continuous, near-isotropic flux of nuclei accelerated outside the solar system: mostly protons, about a tenth helium, and a small fraction of heavier nuclei up to iron. That last fraction is the difficulty. High-energy heavy ions, known as HZE particles, carry energies in the hundreds of MeV per nucleon and deposit dense, correlated tracks of ionisation as they pass through tissue. The result is clustered DNA lesions, which repair machinery handles far worse than the sparse damage from X-rays. Flux varies inversely with the solar cycle, roughly doubling between solar maximum and minimum. Solar particle events are episodic bursts, overwhelmingly protons, associated with flares and coronal mass ejections. They are unpredictable and can last hours to d","c":["space","genetics"],"k":"concept","x":"speculative","h":"2040s","w":1363,"n":7},{"s":"rapamycin","t":"Rapamycin","d":"A macrolide immunosuppressant that inhibits the mTOR growth pathway and extends lifespan across several laboratory species, with no confirmed effect on human aging.","g":["mtor","aging","drug repurposing","autophagy","immunosenescence","clinical trials"],"b":"Rapamycin is a bacterial macrolide, marketed as sirolimus, that inhibits the mechanistic target of rapamycin (mTOR), the kinase complex through which cells decide whether conditions favour growth or conservation. It is one of the few compounds shown to extend lifespan in yeast, nematodes, flies and mice, and it is the most reproducible positive result in the US National Institute on Aging's Interventions Testing Program. Whether it does anything for human aging is unknown. The lifespan evidence comes from mice. A randomized lifespan trial in pet dogs has not reported, and no primate survival data have been published in a peer-reviewed journal. The human trials run so far have tested immune, body-composition and functional surrogates in small populations, and the one large randomized trial of a related compound failed its primary endpoint. How it works mTOR sits at the centre of nutrient sensing. As part of complex 1 (mTORC1) it integrates amino-acid availability, growth-factor signalling and cellular energy state. When those inputs are favourable, it drives protein synthesis through S6 kinase and 4E-BP1, promotes ribosome biogenesis and suppresses Autophagy. Rapamycin does not bind mTOR directly. It first binds the small protein FKBP12, and the resulting complex docks onto mTORC1 and restricts its activity allosterically. Inhibiting mTORC1 therefore shifts a cell from building ","c":["longevity"],"k":"intervention","x":"experimental","h":"2030s","w":2173,"e":"No human trial has tested lifespan or aging; low-dose mTOR inhibitors improved flu vaccine response, a phase 3 trial of one failed, and a 48-week rapamycin trial missed its primary endpoint.","a":"Approved as sirolimus for transplant rejection and available as a generic; longevity use is off-label prescribing by a minority of physicians, at doses and schedules no regulator has evaluated.","r":"reversible","n":46},{"s":"ray-kurzweil","t":"Ray Kurzweil","d":"American inventor and futurist who formulated the law of accelerating returns and forecasts human-level machine intelligence by 2029 and a technological singularity by 2045.","g":["singularity","forecasting","artificial intelligence","futurism","life extension"],"b":"Ray Kurzweil is an American inventor, computer scientist and futurist. His reading of technological history holds that information technologies improve exponentially rather than linearly, and that the exponent itself is stable across substrates; on that basis he forecasts a Technological singularity around 2045. He built a substantial engineering career in pattern recognition before becoming the most widely read forecaster of machine intelligence, and he is a prominent proponent of radical life extension. Career Kurzweil built a pattern-recognition program that matched high-school students to colleges while still in high school, and studied at MIT under Marvin Minsky. His inventions cluster around reading and hearing. In the mid-1970s he combined the first omni-font optical character recognition with a flatbed scanner and a speech synthesizer to produce the Kurzweil Reading Machine, a print-to-speech device for blind readers developed with the National Federation of the Blind. He later founded Kurzweil Music Systems, whose K250 synthesizer reproduced sampled acoustic instruments, and Kurzweil Applied Intelligence, an early large-vocabulary speech-recognition company. He received the National Medal of Technology in 1999 and entry to the National Inventors Hall of Fame in 2002. In 2012 he joined Google as a director of engineering working on natural-language understanding; his ow","c":["people","minds"],"k":"person","x":"contested","h":"present","w":1014,"n":11},{"s":"reproductive-longevity","t":"Reproductive longevity","d":"The functional lifespan of the reproductive system, and efforts to extend it in the ovary, which loses function decades before most other organs.","g":["aging","ovary","menopause","fertility","oocyte","healthspan"],"b":"Reproductive longevity is the duration over which the reproductive system remains functional, and, as a research programme, the attempt to extend it. In women the relevant organ is the ovary, which loses most of its function around the age of 51 while the heart, liver, and brain are still decades from failure. That asymmetry makes the ovary the clearest example in human biology of an organ ageing on its own schedule, and it has made the field a testbed for the wider claims of the Geroscience hypothesis. The uterus is not the limiting organ. It can carry a pregnancy well after menopause when donated oocytes are used, and Uterus transplantation has produced live births in women who had no working one of their own. Two clocks in one organ The ovary declines along two axes, and the two are often conflated. Quantity. Germ cells reach their maximum number in mid-gestation, at several million, and fall continuously thereafter through atresia, a programmed loss largely independent of ovulation. By puberty a few hundred thousand primordial follicles remain; by menopause, a few hundred. Clinically this pool is estimated by anti-Müllerian hormone in blood and by antral follicle count on ultrasound, neither of which reliably predicts when an individual will reach menopause. Quality. From the mid-thirties, the proportion of eggs that segregate their chromosomes correctly falls steeply. The ","c":["reproduction","longevity"],"k":"concept","x":"emerging","h":"2030s","w":1448,"e":"Oocyte and ovarian tissue cryopreservation are established practice in women, but no intervention has been shown to delay human menopause; the rapamycin work reports surrogate ovarian-reserve measures in a small group.","n":14},{"s":"respirocytes","t":"Respirocytes","d":"Robert Freitas's 1998 design study for an artificial red blood cell built as a pressurised micron-scale gas tank, widely cited and never built.","g":["nanomedicine","nanorobotics","blood","oxygen","design study","enhancement"],"b":"Respirocytes are a proposed artificial replacement for the red blood cell: micron-scale pressure vessels that would load oxygen in the lungs, release it in tissue, and carry carbon dioxide back, storing both gases at pressures far beyond anything haemoglobin achieves. The design was published by Robert Freitas in 1998 and has been reproduced in popular accounts of nanomedicine ever since. It is a calculation, not a device; nothing resembling a respirocyte has been fabricated, and the manufacturing method it assumes has never been demonstrated. Overview A red blood cell carries oxygen by reversible binding to haemoglobin. Freitas proposed carrying it as compressed gas instead. A respirocyte, in his description, is a roughly spherical vessel about a micrometre across with separate high-pressure chambers for oxygen and carbon dioxide, an outer hull of diamondoid carbon, molecular sorting rotors in the wall that pump specific gas molecules in or out, an onboard sensor and computer to decide when to load and unload, and a glucose engine drawing fuel from blood plasma. Because gas under roughly a thousand atmospheres is far denser than gas bound to protein, the device would carry much more oxygen per unit volume than the cell it replaces. Freitas put the advantage at 236 times that of a natural red cell and suggested that an injection of a concentrated suspension containing trillions","c":["nanomedicine"],"k":"concept","x":"speculative","h":"indefinite","w":1329,"e":"No respirocyte has been built, so none has been tested in any person or animal; the published performance figures are outputs of a 1998 physical model rather than measurements.","n":9},{"s":"retatrutide","t":"Retatrutide","d":"An investigational once-weekly injectable peptide from Eli Lilly that activates the GIP, GLP-1 and glucagon receptors, in phase 3 trials for obesity and type 2 diabetes.","g":["obesity","incretins","diabetes","clinical trials","metabolic health","drug access"],"b":"Retatrutide is an investigational drug developed by Eli Lilly: a single engineered peptide that activates three hormone receptors, those for GIP, GLP-1 and glucagon, and is injected once a week. In phase 3 trials it has produced mean weight losses of up to about a quarter of body weight in adults with obesity, along with lower blood glucose in people with type 2 diabetes. As of November 2026 it is approved nowhere, and the trials that would show whether it prevents heart attacks, kidney failure or death are still running. How it works Retatrutide extends the incretin approach behind the Glp 1 receptor agonists. GLP-1 agonists such as semaglutide act on one receptor; tirzepatide acts on two, GIP and GLP-1; retatrutide adds a third, the receptor for glucagon. Lilly's discovery paper describes it as a peptide with balanced glucagon and GLP-1 receptor activity in cell assays and stronger activity at the GIP receptor. Its half-life in people with type 2 diabetes is about six days, which is what allows weekly dosing. The glucagon arm is the novel part, and it is counterintuitive because glucagon raises blood glucose. The rationale comes from animal work. In obese mice the drug's weight loss was larger than appetite suppression alone explained, and the authors attributed the extra loss to glucagon-driven increases in energy expenditure. That is a mouse result. In people, the clearest ","c":["longevity","society"],"k":"intervention","x":"experimental","h":"late 2020s","w":2188,"e":"Phase 3 randomized trials in several thousand adults with obesity or type 2 diabetes show large weight loss and lower HbA1c over 40-80 weeks; the dedicated cardiovascular and kidney outcome trial has not reported, and no registered trial has an aging endpoint.","a":"Not approved anywhere as of November 2026; outside Lilly's trials it is available only through a narrow single-patient expanded access programme; unapproved 'research use' products are sold online, and the FDA says retatrutide cannot be lawfully compounded.","r":"reversible","n":2},{"s":"retinal-implant","t":"Retinal implants and visual prostheses","d":"Implanted devices that restore rudimentary vision to blind people by electrically stimulating surviving retinal neurons or, more invasively, the visual cortex.","g":["vision","sensory restoration","implants","blindness","neuroprosthetics","phosphenes"],"b":"Retinal implants and visual prostheses are devices that produce visual sensation in blind people by stimulating the surviving parts of the visual pathway with electric current. They target conditions in which the photoreceptors have died but the downstream retina and optic nerve remain largely intact, chiefly retinitis pigmentosa and the geographic atrophy form of age-related macular degeneration. Every device fielded so far produces vision built from phosphenes, discrete spots of light with no colour and little detail, and no system has restored acuity anywhere near the legal threshold for blindness. How it works A camera, usually mounted on spectacles, captures a scene. A processor reduces the image to a low-resolution activation map and transmits it to an implanted array, which converts each pixel into a current pulse delivered to nearby retinal neurons. The retina is a layered circuit rather than a screen, so where the electrodes sit changes what they excite. Epiretinal arrays sit on the inner retinal surface and stimulate retinal ganglion cells, the output neurons whose axons form the optic nerve. This bypasses all the intervening retinal processing, so the signal that reaches the brain is not the code the retina would normally send. Axons of passage from distant regions are stimulated as well, producing elongated or displaced phosphenes. Argus II was the leading epiretina","c":["cybernetics"],"k":"technology","x":"experimental","h":"late 2020s","w":1336,"e":"Devices have been implanted in blind people for over a decade; the strongest result is a 2025 European trial in which most PRIMA recipients identified letters and read words under electronic magnification.","a":"Both commercially approved devices have been withdrawn and existing recipients have lost manufacturer support; access now runs through clinical trials, chiefly of the PRIMA subretinal system, at device-plus-surgery costs among the highest in ophthalmology.","r":"difficult","n":12},{"s":"retro-biosciences","t":"Retro Biosciences","d":"A longevity biotechnology company funded by Sam Altman with the stated goal of adding ten years of healthy life, working on autophagy, reprogramming and plasma-inspired therapies.","g":["aging","autophagy","reprogramming","biotech","protein engineering","healthspan"],"b":"Retro Biosciences is a privately held longevity company founded in 2021 and funded initially with $180 million from Sam Altman, with the stated objective of adding ten years to healthy human lifespan. It runs three programmes: small molecules that enhance Autophagy, cellular reprogramming, and therapies derived from the young-plasma literature. In public it is more specific than its better-funded peers about programmes, goals and timelines. Most of the attention it receives has come from an early collaboration with OpenAI on protein design. Overview The company frames its work more narrowly than the field's usual rhetoric, and does so deliberately. Rather than treating aging as a single process to be reversed, it selected three mechanisms with existing preclinical support and organized itself around getting each into humans. Joe Betts-LaCroix, a hardware engineer turned entrepreneur who previously co-founded a computing company and had been involved in longevity advocacy, is chief executive. Retro has an order of magnitude less capital than Altos labs, and its public posture is correspondingly more concrete. It names its programmes, states a numerical goal, and has discussed clinical timelines, none of which its larger competitor does. History The company was formed in 2021 and operated quietly until March 2023, when MIT Technology Review reported that Sam Altman, then chief ex","c":["organizations","longevity"],"k":"organization","x":"emerging","h":"2030s","w":1099,"n":11},{"s":"right-to-die-and-right-to-live","t":"Right to die and the duty to live","d":"How the law and ethics of assisted dying interact with radical life extension, and whether an indefinitely extendable life could still be voluntarily ended.","g":["bioethics","law","assisted dying","autonomy","aging","mortality"],"b":"Right to die and the duty to live names the intersection of two bodies of argument that developed separately and are beginning to collide: the law and ethics of assisted dying, built around people whose deaths are near and unwanted, and the prospect of interventions that make continued life a standing option rather than a fixed allotment. If aging becomes treatable, refusing treatment becomes a choice, and every question about whether death may be chosen acquires a mirror image about whether life may be declined. Two doctrines, separately built Modern end-of-life law rests on a distinction that is legally stable in most jurisdictions but philosophically contested. A competent person may refuse any medical treatment, including life-sustaining treatment, and this right is close to absolute. Whether anyone may assist them to die actively is a separate question that most legal systems answer differently. The US Supreme Court set out both halves in the 1990s. A 1990 case established a constitutionally protected liberty interest in refusing unwanted medical treatment, and two 1997 decisions held that there is no corresponding constitutional right to assistance in suicide, leaving the question to the states. Oregon's statute, in force from 1997, permits a physician to prescribe lethal medication to a terminally ill adult who self-administers it; roughly a dozen US jurisdictions now ha","c":["society","longevity"],"k":"concept","x":"contested","h":"present","w":1505,"n":8},{"s":"robert-freitas","t":"Robert Freitas","d":"American researcher whose Nanomedicine volumes set out detailed numerical designs for medical nanorobots, among them the respirocyte, none of which has been fabricated.","g":["nanotechnology","nanomedicine","nanorobots","molecular manufacturing","self-replication","cryonics"],"b":"Robert Freitas is an American researcher who has spent three decades producing detailed engineering analyses of machines that do not exist. His four-volume Nanomedicine, of which two volumes have appeared, works through the physics of micron-scale devices intended to operate inside the human body: power, heat, navigation, sensing, communication, and what happens when a rigid manufactured object meets blood. The best known of the designs is the respirocyte, an artificial red cell. None of the devices has been fabricated, and Freitas has been consistent that his work is not a prediction that any of them will be. Overview Freitas works in a genre he calls exploratory engineering: analysis intended to establish that a proposed device violates no physical law and to bound its performance if built, while deliberately setting aside how anyone would build it. The output is a specification and a set of numbers rather than an experiment. As engineering analysis the volumes are unusually thorough. As evidence that Medical nanorobots are coming they establish nothing, because a design can be consistent with physics and still impossible to make. Most of the argument about his work comes down to which of the two it is being read as. Career Freitas took degrees in physics and psychology at Harvey Mudd College and a law degree at Santa Clara University. His early work was in exobiology rather ","c":["people","nanomedicine"],"k":"person","x":"contested","h":"present","w":1303,"n":1},{"s":"robotic-avatars","t":"Robotic avatars","d":"Robots driven in real time by a remote human operator who sees, hears and feels through them, also called telexistence or immersive telepresence robotics.","g":["robotics","teleoperation","telepresence","haptics","virtual reality","human augmentation","wearables"],"b":"Robotic avatars are robots that a human operator drives in real time from somewhere else, seeing through the robot's cameras, hearing through its microphones and, in the more capable systems, feeling the forces its hands meet. Susumu Tachi named the idea \"telexistence\" in 1980, and Marvin Minsky's \"telepresence\", proposed independently the same year, covers much the same ground. The ANA Avatar XPRIZE, a $10 million competition for such systems, was announced in 2018 and decided in 2022. What separates an avatar from an ordinary remote-controlled machine is the aim of embodiment: the operator should act through the robot as though it were their own body, rather than steer it from a console. How it works An avatar system has an operator station, a robot and a network between them. The operator usually wears a head-mounted display fed by stereo cameras on a robot head that follows the operator's own head movements. Operators often get motion sickness while the robot is moving, because its camera image is not stabilized the way the eye's image is, and delay in the video stream can make this worse. The winning XPRIZE team hid head-motion latency with a technique it calls spherical rendering. Arm control comes in two broad forms. In task-space control the station tracks only the operator's hand and software computes how the robot's arm should reach it. In joint-space control the oper","c":["enhancement","cybernetics"],"k":"technology","x":"emerging","h":"2030s","w":2406,"e":"Operators have run avatar systems in competition trials and small laboratory user studies of mostly young adults; published evaluations come from short sessions on test courses, not from real hazardous work.","a":"Most immersive avatar systems are research prototypes; a few companies supply teleoperated robots to businesses, and the published examples disclose no prices.","r":"reversible","n":2},{"s":"sarcopenia","t":"Sarcopenia","d":"The age-related loss of skeletal muscle mass, strength and function, the strongest physical predictor of late-life disability and the target of a drug pipeline that has yet to deliver.","g":["aging","muscle","frailty","exercise","clinical trials","geriatrics"],"b":"Sarcopenia is the progressive loss of skeletal muscle mass, strength and function that accompanies aging. It begins quietly in mid-adulthood, accelerates after about sixty, and by late life is the main physical substrate of frailty: it can decide whether a person rises from a chair unaided, or whether a stumble ends in recovery or a fractured hip. It is also a test case for geroscience. In sarcopenia the best treatment is unambiguous, cheap, and not a drug, and the drug pipeline built to supplement it has so far added muscle without adding function. From adjective to diagnosis Physicians have described muscle wasting in the old for as long as medicine has described the old, but the condition had no name and therefore no research programme. In 1989 the nutritionist Irwin Rosenberg, closing a meeting on nutrition and aging, argued that no decline with age is more dramatic or functionally significant than the loss of lean body mass. He proposed giving it a Greek name, sarcopenia (\"poverty of flesh\"), so that it would be studied and measured instead of accepted. The naming worked, slowly. The European Working Group on Sarcopenia in Older People (EWGSOP) published the first widely adopted operational definition in 2010, combining low muscle mass with low strength or performance; its 2019 revision, EWGSOP2, inverted the order, making low strength the primary criterion, muscle quantit","c":["longevity","bodies"],"k":"concept","x":"established","h":"present","w":1436,"e":"Resistance training improves strength and function in randomised trials into the tenth decade of life; every drug candidate so far has added lean mass without demonstrating added function, and none is approved.","n":3},{"s":"senolytics","t":"Senolytics","d":"Drugs that selectively kill senescent cells, an approach that reduces age-related pathology in mice but has so far produced modest or null results in humans.","g":["cellular senescence","aging","sasp","clinical trials","drug repurposing","apoptosis"],"b":"Senolytics are drugs that kill senescent cells selectively while leaving dividing and quiescent cells intact. The class was proposed in 2015 on the reasoning that senescent cells survive despite extensive damage because they upregulate a small number of anti-apoptotic pathways, and that transiently blocking those pathways would tip them into cell death. In mice, clearing senescent cells improves function in a long list of tissues and has been reported to extend lifespan. In humans the completed trials have been small, mostly uncontrolled, and their results have been modest or negative. How they work Senescent cells have withdrawn stably from the cell cycle but remain metabolically active. They enlarge, resist apoptosis, and secrete a mixture of cytokines, chemokines, proteases, and growth factors known as the senescence-associated secretory phenotype (SASP), characterized in the 2000s by groups including those at the Buck institute. The SASP is what makes senescent cells plausible drivers of aging rather than inert debris, and its paracrine spread links the process to Inflammaging and to Stem cell exhaustion. Cells reach the state by several routes: telomere attrition in replicative senescence, DNA damage, oncogene activation, and severe mitochondrial stress. The variety of routes is one reason the resulting populations are not biochemically uniform. Cellular senescence covers ","c":["longevity"],"k":"intervention","x":"experimental","h":"2030s","w":2010,"e":"Human data are small open-label pilots of nine to fourteen patients, one showing reduced senescent-cell markers in fat and skin, plus two randomized failures; every lifespan result is from mice.","a":"No senolytic is approved for any aging indication; dasatinib is an approved cancer drug available only on prescription, and fisetin and quercetin are sold over the counter as supplements at doses taken from mouse studies.","r":"partly-reversible","n":46},{"s":"sens-research-foundation","t":"SENS Research Foundation","d":"A California nonprofit founded in 2009 to fund rejuvenation research organized around seven categories of accumulated cellular damage, merged into the Lifespan Research Institute in 2024.","g":["aging","damage repair","nonprofit","rejuvenation","research funding","sens"],"b":"SENS Research Foundation is a California nonprofit established in 2009 to fund research on Strategies for Engineered Negligible Senescence, a framework that treats aging as the accumulation of seven classes of cellular and molecular damage, each to be repaired directly rather than prevented. Spun out of the Methuselah foundation by Aubrey de grey and colleagues, it was for a decade the main institutional home of the damage-repair approach to aging. It removed de Grey in 2021 after allegations of misconduct, and in 2024 merged with the advocacy organization Lifespan.io to form the Lifespan Research Institute. Overview The SENS framework makes an engineering claim rather than a biological one. Its proponents argue that removing damage does not require understanding the metabolic processes that generate it, in the same way that a mechanic need not understand combustion chemistry to replace a corroded part. The framework deliberately contrasts with the mainstream Geroscience hypothesis, which seeks to slow damage accumulation by modulating pathways such as mTOR and nutrient sensing with drugs like Rapamycin. It also contrasts with the descriptive Hallmarks of aging framework, which SENS advocates regard as a taxonomy that stops short of telling anyone what to build. The framework enumerates seven damage categories and asserts that the list is complete, in the sense that no new clas","c":["organizations","longevity"],"k":"organization","x":"established","h":"present","w":1363,"n":10},{"s":"sensory-augmentation","t":"Sensory augmentation","d":"Devices and biological modifications that route information the body cannot normally detect into a channel the brain can learn to read.","g":["senses","enhancement","neuroplasticity","implants","perception","sensory substitution"],"b":"Sensory augmentation is the use of devices or biological modification to deliver information a human body cannot normally detect (magnetic north, infrared, seismic activity, air quality) through a sensory channel that can carry it. What separates it from sensory substitution, which routes information from a lost sense through a surviving one, is mainly intent. The hardware and the neuroscience are largely the same, and most augmentation work descends directly from substitution research done for blind and deaf users. How it works Every approach follows the same three steps: capture a signal with a sensor, compress it into a low-bandwidth code, and deliver that code through skin, hearing, or another intact channel. The brain is expected to do the rest. The binding constraint is bandwidth. The optic nerve carries roughly a million axons, while a tactile array on the back or a vibrating wristband delivers a few dozen distinguishable channels at best. Every substitution device therefore throws away nearly all of the information it captures, and the design problem is choosing which fraction to keep. This is why devices for navigation and obstacle avoidance work reasonably well and devices intended to convey scenes do not. The second requirement is that the signal be coupled to action. Perceptual learning depends on the user changing the input by moving; a passive stream of vibration ","c":["enhancement","cybernetics"],"k":"technology","x":"experimental","h":"late 2020s","w":1301,"e":"In people only worn devices and subdermal magnets have been used; the Osnabrück magnetic-north belt produced measurable navigation and cortical changes after weeks of wear, and the biological routes to a new channel exist only in monkeys and mice.","a":"Tactile and auditory substitution devices are cleared and sold as assistive equipment in some jurisdictions; augmentation devices such as magnetic-north wearables and subdermal fingertip magnets are unregulated consumer items.","r":"reversible","n":12},{"s":"shinya-yamanaka","t":"Shinya Yamanaka","d":"Japanese physician-scientist who showed that four transcription factors can reprogram adult cells to a pluripotent state, sharing the 2012 Nobel Prize for the discovery.","g":["stem cells","reprogramming","ipsc","nobel prize","regenerative medicine"],"b":"Shinya Yamanaka is a Japanese physician-scientist who demonstrated in 2006 that introducing four transcription factors into an adult mouse fibroblast can return it to an embryonic-like pluripotent state, and repeated the result in human cells the following year. The four factors (Oct3/4, Sox2, Klf4 and c-Myc) are now known as the Yamanaka factors, and the cells they produce as Induced pluripotent stem cells. He shared the 2012 Nobel Prize in Physiology or Medicine with John Gurdon. Career Yamanaka trained as an orthopedic surgeon at Kobe University. He has described that period as unsuccessful: he was slow in the operating theatre and found the limits of surgical repair frustrating. He moved into research and completed a doctorate in pharmacology at Osaka City University in 1993. A postdoctoral position at the Gladstone Institutes in San Francisco taught him American laboratory culture and, in his own account, the value of pursuing unexpected results: a transgenic mouse experiment aimed at cholesterol metabolism instead produced tumours, which redirected his attention to gene regulation. Returning to Japan, he held positions at Osaka City University and the Nara Institute of Science and Technology before moving to Kyoto University in 2004. In 2010 he became the founding director of the Center for iPS Cell Research and Application (CiRA) at Kyoto, which he led until 2022; he rem","c":["people","genetics"],"k":"person","x":"established","h":"present","w":996,"n":6},{"s":"singularitarianism","t":"Singularitarianism","d":"The belief that a technological singularity is likely and that it should be actively prepared for, together with the movements organized around that belief.","g":["singularity","artificial intelligence","movements","transhumanism","ai safety","forecasting"],"b":"Singularitarianism is the position that a Technological singularity is likely within a foreseeable period and that this warrants a deliberate response now, along with the loose set of movements built around that position. It is distinct from the singularity hypothesis itself, which a person can hold without any accompanying commitment about what to do. A singularitarian adds the second half: the belief that the transition is important enough, and near enough, to organize one's work or one's institution around. Overview The label was applied within the extropian community around 1991 and used through the 1990s as a self-description. By the mid-2000s it had two very different referents. Ray kurzweil used it in The Singularity Is Near to describe someone who understands the coming transition and plans their life accordingly, with an emphasis on personal survival to reach it. Eliezer Yudkowsky, in a set of essays written around 2000, defined it as a commitment to bring about a beneficial singularity and treated the safety of the transition as the whole point. The two readings diverged into institutional traditions that still barely speak to one another, and the word is now used more often by critics than by adherents. Origins Three texts do most of the work. I. J. Good's 1965 paper describes the mechanism. Vernor Vinge's 1993 essay names the event and argues that it ends the era of","c":["people","minds"],"k":"concept","x":"contested","h":"indefinite","w":1206,"n":8},{"s":"sleep-and-longevity","t":"Sleep and longevity","d":"Habitual sleep duration and timing, an exposure tied to mortality in large observational cohorts and almost untested as a deliberate intervention to extend life.","g":["sleep","circadian rhythm","epidemiology","aging","healthspan","causal inference"],"b":"Sleep and longevity describes the relationship between how long and how well a person sleeps and how long that person lives. It is one of the most consistently reproduced associations in observational epidemiology: across large prospective cohorts, both short and long habitual sleep track higher all-cause mortality. It is also one of the thinnest interventional literatures in geroscience. No randomized trial has tested whether making people sleep more makes them live longer, and the mechanism most often invoked to explain why it should is currently disputed. The epidemiological signal A meta-analysis of prospective cohorts published in 2010 established the shape that later work has mostly confirmed: mortality is elevated among people reporting short sleep, variously defined as below about six or seven hours, and also among those reporting long sleep, above about eight or nine. The curve is not a straight line, and the two tails do not carry the same interpretation. The relative risks are modest, tens of percent above the reference category rather than multiples of it, and small enough that residual confounding remains a live explanation for either tail. The long-sleep tail is widely read as reverse causation. Cancer, heart failure, depression, infection, and the drugs used to treat them all increase time spent asleep or in bed, so a person sleeping ten hours is often a person w","c":["longevity"],"k":"intervention","x":"established","h":"present","w":1789,"e":"Large prospective cohorts link both short and long habitual sleep to higher mortality, and short randomized trials of sleep extension have moved metabolic measures; no trial has tested survival.","a":"Free and in principle universal, but bounded by shift schedules, caregiving, noise, light, housing, and untreated sleep disorders, none of which a recommendation reaches.","r":"reversible","n":15},{"s":"somatic-gene-therapy","t":"Somatic gene therapy","d":"Genetic modification of a living person's body cells to treat disease, producing a change that is not passed on to their children.","g":["gene therapy","rare disease","aav","drug pricing","clinical trials","cell therapy"],"b":"Somatic gene therapy is the deliberate alteration of genetic material in a living person's body cells (as distinct from their eggs, sperm, or embryos) in order to treat or prevent disease. Because the modified cells lie outside the germ line, the change ends with the patient and is not inherited, which is the line that separates the practice legally and ethically from Germline editing. As of 2026 more than twenty gene and gene-modified cell therapies hold marketing authorisation in the United States, nearly all of them for rare single-gene disorders or for blood cancers. How it works Three problems have to be solved: what to change, how to get the change into the right cells, and how to make it last. The first is the easiest. Thousands of diseases trace to a defined mutation, and for many the therapeutic logic is simply to supply a working copy of the gene, silence a toxic one, or repair the sequence in place with Crispr cas9, Base editing, or Prime editing. Delivery is where most programmes fail. Two broad strategies exist. Ex vivo therapy removes a patient's cells, usually CD34+ haematopoietic stem cells or T cells, modifies them in a laboratory, and returns them. This gives complete control over the editing step and allows the modified cells to be characterised before infusion, at the cost of an intensive clinical procedure. In vivo therapy injects the vector into the patien","c":["genetics","bodies"],"k":"intervention","x":"established","h":"present","w":1246,"e":"Licensed products treat inherited retinal dystrophy, sickle cell disease and spinal muscular atrophy in people; durability varies, and clotting-factor expression after haemophilia gene therapy declines over the years after treatment.","a":"Approved in the US and Europe for a short list of rare diseases and blood cancers, delivered at a small number of specialist centres; list prices run from roughly $400,000 to $4.25 million per patient.","r":"context","n":48},{"s":"space-medicine","t":"Space medicine","d":"The medical discipline concerned with how spaceflight alters human physiology and with keeping crews functional in an environment the body did not evolve for.","g":["spaceflight","microgravity","radiation","bone loss","physiology","aging","countermeasures"],"b":"Space medicine is the branch of medicine that studies how spaceflight changes the human body and designs the countermeasures, selection standards, and clinical procedures that keep crews alive and capable. It is unusual among medical specialties in that its entire evidence base rests on a cohort of fewer than a thousand people, almost all of them screened for exceptional health before flying. The changes it documents, among them bone loss, muscle wasting, immune dysregulation, vascular stiffening and ocular remodelling, resemble an accelerated version of ordinary biological aging, which is why the field has become relevant to biogerontology. Overview Human physiology is calibrated to a gravitational field of 1 g, a magnetosphere, a 24-hour light cycle, and a microbial and social environment that has been constant for the species' entire history. Orbital flight removes or alters all four at once. The body responds by adapting rather than breaking down, and the adaptations that suit weightlessness work against a returning crew on a planet. Space medicine therefore has two jobs that pull in different directions. Operationally, it must keep a crew functional for the duration of a mission and land them able to walk. Scientifically, it must characterise a set of exposures no ethics board would ever approve as an experiment, using a sample size that would be considered inadequate in a","c":["space","bodies"],"k":"concept","x":"established","h":"present","w":1983,"n":18},{"s":"speech-neuroprosthesis","t":"Speech neuroprosthesis","d":"A brain-computer interface that reconstructs intended speech from motor cortex activity, producing text or synthesized voice for people who cannot speak.","g":["bci","speech decoding","als","anarthria","neural decoding","communication"],"b":"Speech neuroprosthesis is a brain-computer interface that recovers intended speech from neural activity and renders it as text, synthesized voice, or an animated face. It is aimed at people who retain the intention and the neural machinery for speech but have lost the motor pathway: those with amyotrophic lateral sclerosis, brainstem stroke, or severe anarthria from other causes. Between 2021 and 2025 the field moved from decoding a fifty-word vocabulary at a conversational crawl to near-real-time output over vocabularies of a hundred thousand words. By 2026 one participant had used such a system at home for nearly two years, and two companies had begun small feasibility trials of fully implanted wireless versions. These systems decode attempted articulation rather than thought. The signals come from the region of cortex that would drive the lips, jaw, tongue and larynx. The decoder recovers a motor plan, and language models turn that noisy plan into plausible sentences. The distinction governs both what the technology can do and which privacy risks it does and does not create. How it works Speech production has a somatotopic map. Along the ventral part of the precentral gyrus, cortical populations encode the movements of individual articulators, and this organization persists in people who have been unable to speak intelligibly for years; the map does not disappear when the ou","c":["cybernetics"],"k":"technology","x":"experimental","h":"2030s","w":2447,"e":"Peer-reviewed results come from single implanted participants or groups of up to four, mostly with ALS or brainstem stroke; one man has used a system at home for nearly two years, and no efficacy trial has reported.","a":"Not obtainable: research implants at academic centres and in small company feasibility studies, all investigational, with no approved or purchasable system as of October 2026.","r":"difficult","n":12},{"s":"stem-cell-exhaustion","t":"Stem cell exhaustion","d":"The age-related decline in the number and regenerative function of adult stem cells across blood, muscle, gut and skin, and the loss of repair capacity that follows.","g":["aging","stem cells","regeneration","clonal hematopoiesis","niche","mechanisms"],"b":"Stem cell exhaustion is the progressive failure of adult stem and progenitor cells to maintain and repair the tissues they serve. It is classified as an integrative hallmark in the Hallmarks of aging framework, meaning it is understood as a consequence of upstream damage that becomes a cause of visible decline in its own right. The term is slightly misleading: in several tissues the number of stem cells stays constant or rises with age while their per-cell function falls. Blood The haematopoietic system is the best-characterized case because its stem cells can be purified, counted, and functionally tested by transplantation. Aged mouse haematopoietic stem cells are more numerous than young ones but reconstitute an irradiated recipient less well, and they produce a skewed output: more myeloid cells, fewer lymphoid. The human correlate is a shrinking naive T-cell pool, weakened responses to new vaccines, and thymic involution that begins in childhood and is largely complete by middle age. Clonal hematopoiesis The most consequential discovery in this area is clonal hematopoiesis of indeterminate potential, or CHIP: the expansion of a single mutant stem cell clone to a detectable fraction of blood cells in people with no blood disorder. Two 2014 studies identified it in large sequencing datasets, found that it becomes common after age 60, and showed that carriers face elevated risk","c":["longevity","bodies"],"k":"concept","x":"established","h":"present","w":1110,"e":"Human sequencing establishes clonal hematopoiesis after 60 and a sharp fall in blood clonal diversity after about 70; the senolytic and reprogramming rejuvenation results are from mice.","n":32},{"s":"synthetic-embryos","t":"Stem-cell-based embryo models","d":"Structures grown by aggregating stem cells that reproduce stages of early embryonic development without fertilisation, and the regulatory categories they fall outside.","g":["embryo models","stem cells","developmental biology","14-day rule","bioethics","regulation"],"b":"Stem-cell-based embryo models are structures assembled from cultured stem cells that reproduce features of early embryonic development without an egg, a sperm, or fertilisation. They are widely called synthetic embryos, a term nearly every researcher in the field objects to. None has produced a live animal in any species, and the most advanced human versions self-organise for a period roughly equivalent to the first two weeks of development before deteriorating. They matter because they fall outside the legal definition of an embryo almost everywhere while resembling one closely enough that the exemption has become difficult to defend. What they are Every model starts from pluripotent cells: embryonic stem cell lines, or Induced pluripotent stem cells made by factor-based reprogramming of adult tissue. The models are classified by which parts of the conceptus they include. - Blastoids model the blastocyst. Mouse versions were made in 2018 by combining embryonic and trophoblast stem cells; human blastoids followed in 2021 from two directions, one starting from naive pluripotent cells and one arising during the reprogramming of fibroblasts. They form an outer trophectoderm-like layer, a cluster resembling the inner cell mass, and a cavity, and some attach to cultured endometrial cells in a way that resembles the first step of implantation. - Gastruloids model the body plan withou","c":["reproduction","genetics"],"k":"technology","x":"experimental","h":"late 2020s","w":1484,"e":"Nothing has been done in a person. Human work is confined to cultured cells, and no embryo model in any species has produced a live animal after transfer to a uterus.","a":"Not a product and not for sale: the models are made in research laboratories from pluripotent stem cell lines, and none is offered clinically or reproductively.","r":"context","n":10},{"s":"stentrode","t":"Stentrode","d":"An endovascular brain-computer interface in which a stent carrying electrodes is delivered through the jugular vein into a vein overlying the motor cortex.","g":["bci","endovascular","implants","paralysis","als","neurotechnology"],"b":"Stentrode is a brain-computer interface built into a self-expanding stent. Instead of opening the skull, a neurointerventional radiologist threads the device through the jugular vein into the superior sagittal sinus, the large vein running along the midline of the brain, where it expands against the vessel wall directly above motor cortex. Electrodes on the stent record cortical activity through the vein wall, and a lead runs under the skin of the neck to a telemetry unit implanted in the chest, which transmits wirelessly to an external computer. The design gives up signal quality in exchange for surgical accessibility. Its sixteen electrodes record population-level activity rather than individual neurons, so the Stentrode captures far less information than a penetrating Utah array. It also needs no craniotomy, relies on catheter techniques that thousands of clinicians already practise, and places no foreign material in the brain parenchyma. How it works The stent is a nitinol mesh of the type used to treat venous stenosis, with electrode contacts mounted on its struts. It is delivered collapsed inside a catheter, self-expands on release, and presses the electrodes against the endothelium. Over the following weeks the vessel wall incorporates the stent. This is the same endothelialization that makes vascular stents stable, and here it fixes the electrodes in position without su","c":["cybernetics"],"k":"technology","x":"experimental","h":"late 2020s","w":1117,"e":"A small number of people with severe paralysis, mostly from ALS, have used the implant for discrete computer control over months to years; the published safety series covers four Australian participants.","a":"Investigational only: implants have been placed solely within the SWITCH and COMMAND feasibility studies at a handful of centres, with no market authorisation anywhere and nothing on sale.","r":"difficult","n":10},{"s":"steve-horvath","t":"Steve Horvath","d":"German-American biostatistician who built the first multi-tissue epigenetic clock, giving aging research a quantitative readout it could test and argue about.","g":["epigenetics","biomarkers","aging","dna methylation","biostatistics","measurement"],"b":"Steve Horvath is a German-American biostatistician who in 2013 published a predictor that estimates a person's chronological age from DNA methylation at a few hundred positions in the genome, and does so across most human tissues. The model, generally known as the Horvath clock, turned an intuition that bodies age at different rates into a number that could be measured, compared between cohorts, and disputed. Most subsequent methylation clocks are either refinements of it or reactions against its design. Overview Horvath is a statistician by trade rather than a bench biologist, and the clock reflects that origin. It was fitted, not derived from a theory of what ages cells: a penalised regression was run over methylation arrays until a small subset of sites reproduced the calendar. That method accounts for both the clock's reach and its central weakness, and Horvath has generally been more explicit about the weakness than his field's publicity has been. Before the clock he was known for network methods in genomics. Weighted gene co-expression network analysis, developed with colleagues at UCLA in the mid-2000s, groups genes into correlated modules and remains one of the most widely used tools in transcriptomics. The habit of looking for structure in high-dimensional measurement, rather than for a mechanism, carried directly into the aging work. Career Horvath trained first in ma","c":["people","longevity"],"k":"person","x":"established","h":"present","w":1332,"n":8},{"s":"substrate-independence","t":"Substrate independence","d":"The claim that mental states depend on a system's functional organization rather than on the material implementing it, so that a mind could run on non-biological hardware.","g":["functionalism","consciousness","philosophy of mind","uploading","multiple realizability","qualia"],"b":"Substrate independence is the thesis that what makes a physical system have mental states is the pattern of causal relations among its parts, not the stuff those parts are made of. If it is true, a system built from silicon, or from any other medium that reproduces the relevant organization, would have the same mental states as a brain reproducing the same organization, including, on the strong reading, the same conscious experience. The thesis is the load-bearing philosophical premise for Mind uploading, Whole brain emulation, and most arguments that a machine could be conscious. It is not established, and the strong reading is actively disputed. The argument The ancestor of the thesis is multiple realizability, proposed by Hilary Putnam in 1967: pain cannot be identical to a specific brain-state type, because octopuses, humans, and hypothetical silicon creatures could all be in pain while sharing no neural type. What they share is a functional role: a state caused by tissue damage, causing avoidance and complaint. If mental kinds are functional kinds, then any system that fills the role has the mental state, whatever it is made of. Applied to a whole mind, the claim becomes that reproducing the causal organization of a brain at sufficient grain reproduces the mind. The phrase \"sufficient grain\" is doing enormous work: nobody claims that reproducing the organization of a brain","c":["minds","foundations"],"k":"concept","x":"contested","h":"indefinite","w":1402,"n":19},{"s":"synchron","t":"Synchron","d":"A neurotechnology company developing an endovascular brain-computer interface implanted through a blood vessel rather than by opening the skull.","g":["brain-computer interface","endovascular","neurotech","paralysis","clinical trials","implants"],"b":"Synchron is a neurotechnology company developing the Stentrode, a Brain computer interface built into a vascular stent and delivered through the jugular to a vein on the surface of the motor cortex, so that no craniotomy is needed. Founded in Melbourne in 2012 and now headquartered in New York, it began implanting patients in Australia in 2019 and in the United States in 2022. It has pursued a deliberately low-bandwidth strategy, in contrast to competitors chasing channel count. Overview The company's strategic premise is that BCI deployment is limited less by the number of neurons recorded than by the willingness of surgeons, regulators and patients to accept an implant. Open-skull electrode arrays require neurosurgery, carry infection and haemorrhage risk, and are performed at a small number of centres. Endovascular delivery, by contrast, is a procedure that interventional neuroradiologists already perform thousands of times a year for stroke and aneurysm, using equipment that most large hospitals already have. The argument is explicitly modelled on the diffusion of the Cochlear implant and of Deep brain stimulation, both of which reached large patient populations only once the implantation procedure became routine. The price of that choice is signal. The Stentrode carries sixteen electrodes inside a vessel wall, separated from cortex by the vessel and by tissue, and it recor","c":["organizations","cybernetics"],"k":"organization","x":"emerging","h":"late 2020s","w":1339,"n":8},{"s":"synthetic-genomes","t":"Synthetic genomes","d":"Genomes designed on a computer and assembled from chemically synthesized DNA, then installed in a cell to see whether the design lives.","g":["synthetic biology","dna synthesis","genome engineering","minimal cell","biosecurity"],"b":"Synthetic genomes are chromosomes designed as text and then built as molecules: an organism's genetic instructions written in a design file, assembled from short synthetic DNA fragments, and installed in a cell to see whether it functions. The aim is to test nature rather than to copy it. A designed genome states exactly which genes an experimenter believes are necessary and which changes are tolerable, and the cell either grows or it does not. That makes genome writing a comprehension test as much as an engineering achievement; the field's founders argue that what cannot be built is not understood. How genomes are built Chemical DNA synthesis produces reliable strands only up to a few hundred bases, so every genome-scale project is an exercise in hierarchical assembly. Short oligonucleotides are joined into fragments of a few kilobases, those into chunks of tens of kilobases, and chunks into megabase assemblies, usually by exploiting yeast's efficient homologous recombination to stitch overlapping pieces together inside a living cell. Errors accumulate at every stage and must be sequenced out. The final step is the hard one. A completed synthetic chromosome must displace the native one. In bacteria this has been done by transplanting a whole genome into a recipient cell emptied of its own, the approach that produced the first cell running on a synthesized chromosome in 2010; i","c":["genetics"],"k":"technology","x":"experimental","h":"2040s","w":1336,"e":"Nothing has been done in a person. The built genomes are bacterial and yeast, human-directed work is confined to cultured cells, and no synthetic human chromosome exists as of 2026.","a":"Nothing to obtain as a product: genome-scale writing is done by a small number of funded laboratories, while commercial suppliers sell only short DNA fragments, subject to order screening.","r":"irreversible","n":18},{"s":"tardigrade-genes","t":"Tardigrade genes and human cells","d":"The attempt to transfer stress-tolerance proteins from tardigrades into human cells, and the gap between what those experiments showed and how they were reported.","g":["tardigrade","radiation","dna repair","anhydrobiosis","gene transfer","dsup"],"b":"Tardigrade genes and human cells describes a small but heavily publicised research line in which proteins from tardigrades are expressed in mammalian cells to see whether their stress tolerance transfers. Tardigrades are millimetre-scale invertebrates that survive desiccation, freezing, vacuum, and enormous radiation doses. One of their proteins, Dsup, does confer measurable protection against radiation-induced DNA damage in cultured human cells, a result that has been replicated. Almost everything else the popular coverage attached to that result was never shown. What tardigrades actually survive Tardigrades enter cryptobiosis: a reversible, near-total suspension of metabolism triggered by drying, freezing, or oxygen deprivation. The shutdown goes far deeper than the mammalian torpor discussed under Human hibernation, and it maintains no circulation at all. In the desiccated \"tun\" state, body water falls to a few per cent and detectable metabolism approaches zero. Animals have been revived from tuns after years, and dried specimens flown on the FOTON-M3 mission survived direct exposure to space vacuum, with survival falling sharply when solar ultraviolet was added. Radiation tolerance is the property that draws most attention. Lethal doses for tardigrades are measured in thousands of grays, roughly a thousand times the dose that kills a human, and hydrated animals tolerate nea","c":["space","genetics"],"k":"concept","x":"experimental","h":"2040s","w":1136,"e":"No person has received Dsup by any route. Protection has been shown only in cultured human cell lines against acute X-rays; no organism-level radioprotection has been demonstrated in a mammal.","n":4},{"s":"targeted-drug-delivery","t":"Targeted drug delivery","d":"The engineering of carriers and conjugates that concentrate a drug where it is needed, a field whose clinical successes have come from chemistry rather than from nanoparticle targeting.","g":["nanomedicine","drug delivery","oncology","antibody-drug conjugates","pharmacokinetics","nanoparticles"],"b":"Targeted drug delivery is the attempt to concentrate a drug in diseased tissue and keep it out of healthy tissue, either by packaging it in a carrier with favourable biodistribution or by attaching it to a molecule that binds a marker on the target cell. It is the oldest ambition in pharmacology and the most persistently disappointing. The therapies that have actually reached patients work by chemistry and antibody biology rather than by the nanoparticle targeting the field spent four decades pursuing. How it works Two mechanisms are available, and they are usually confused. Passive targeting relies on where a particle goes by default. Carriers between roughly 10 and 200 nanometres circulate longer than free drug, avoid renal filtration, and accumulate preferentially in tissues with leaky vasculature. Tumours were long thought to be such tissues: the enhanced permeability and retention effect, described by Matsumura and Maeda in 1986, holds that fenestrated tumour vessels let macromolecules out and poor lymphatic drainage keeps them there. EPR became the organising rationale for cancer nanomedicine. Active targeting attaches a ligand (an antibody, an aptamer, a peptide, a sugar) that binds a receptor enriched on the target cell. The intuitive picture, in which the ligand steers the carrier, is wrong. Studies comparing antibody-targeted and untargeted liposomes found that target","c":["nanomedicine"],"k":"technology","x":"established","h":"present","w":1360,"e":"Antibody-drug conjugates, sugar-conjugated siRNAs and reformulated carriers are approved and in routine use in patients; no approved nanomedicine's benefit is clearly attributable to EPR targeting.","a":"Approved conjugates and reformulated carriers are prescribed routinely in oncology and rare disease at specialty-biologic prices; carriers targeted to tissues outside the liver exist only in research.","r":"reversible","n":22},{"s":"technological-singularity","t":"Technological singularity","d":"The hypothesized point at which machine intelligence begins improving itself fast enough that technological change outruns human ability to predict or steer it.","g":["singularity","artificial intelligence","forecasting","intelligence explosion","superintelligence","recursive self-improvement"],"b":"Technological singularity is the name given to a hypothesized transition in which machine intelligence becomes capable of improving itself, sets off a feedback loop of accelerating capability gain, and thereby produces a future that human beings cannot forecast because they cannot model the agents driving it. The idea has three distinguishable versions, which are often conflated: a claim about a specific mechanism, a claim about the shape of long-run technological growth, and a claim about the limits of prediction. Nothing about it has been demonstrated, and the disagreement about it runs between serious people rather than between experts and cranks. Overview The word does two jobs. In its mathematical sense a singularity is a point at which a function's value ceases to be defined, as when a curve goes vertical. In its use here it names an event horizon: a moment past which the ordinary methods of forecasting stop returning answers. Both senses are metaphors borrowed to describe the same conjecture, which is that intelligence is the input to technological progress, that intelligence is itself a technology, and that a self-improving process therefore has no obvious external brake. What follows from that conjecture depends heavily on which version is being argued. The mechanism version makes a strong, falsifiable-in-principle claim about what a sufficiently capable system would d","c":["foundations","minds"],"k":"concept","x":"speculative","h":"indefinite","w":1988,"n":15},{"s":"technology-readiness-level","t":"Technology readiness level","d":"A nine-point scale, originating at NASA, that rates how far a technology has moved from observed basic principles to proven operational use.","g":["forecasting","translation","regulation","engineering","clinical trials","methodology"],"b":"Technology readiness level (TRL) is a nine-point ordinal scale that describes how far a technology has progressed from the observation of basic principles toward demonstrated operation in its intended environment. It was created to give programme managers a common vocabulary for maturity, so that a proposal claiming a component was \"ready\" could be interrogated about what exactly had been demonstrated, at what scale, and under what conditions. This wiki assigns a TRL to every article typed as a technology or intervention, which makes the scale's assumptions and its failure modes directly relevant to how those articles should be read. The scale The canonical definitions are: 1, basic principles observed; 2, technology concept formulated; 3, experimental proof of concept; 4, component validated in a laboratory; 5, component validated in a relevant environment; 6, system or subsystem demonstrated in a relevant environment; 7, prototype demonstrated in an operational environment; 8, system complete and qualified; 9, system proven in operation. Two words carry most of the weight. Relevant environment means conditions that reproduce the stresses of the real setting in the respects that matter: vacuum and thermal cycling for a spacecraft component, a living organism for a therapeutic. Operational environment means the actual setting, with all of its uncontrolled variables. The distinc","c":["foundations"],"k":"concept","x":"established","h":"present","w":1372,"n":14},{"s":"telomeres-and-telomerase","t":"Telomeres and telomerase","d":"Repetitive DNA caps that shorten with each cell division, and the enzyme that rebuilds them, linking division limits, cancer risk, and a contested marker of aging.","g":["aging","telomeres","cancer","cell biology","biomarkers","mechanisms"],"b":"Telomeres and telomerase are, respectively, the repetitive nucleotide sequences and associated proteins that cap the ends of linear chromosomes, and the reverse transcriptase that extends them. Telomeres shorten each time a somatic cell divides. When they become critically short, the cell triggers a DNA damage response and enters senescence or apoptosis. Telomere attrition is one of the Hallmarks of aging, but its causal weight in normal human aging is smaller and more disputed than popular accounts suggest. Structure and function Human telomeres consist of thousands of tandem TTAGGG repeats ending in a single-stranded 3′ overhang, which folds back to form a lasso-like t-loop. Six proteins, TRF1, TRF2, POT1, TIN2, TPP1 and RAP1, together called the shelterin complex, bind the repeats and hide the chromosome end from the repair machinery. Without shelterin, the cell reads a natural chromosome terminus as a double-strand break and tries to fuse it to another chromosome, producing the end-to-end fusions and breakage cycles that characterize genomic crisis. What matters is the capping function, not the length as such. A telomere can be long and dysfunctional if shelterin is disrupted, and short telomeres in a cell with intact capping may not signal damage until a threshold is crossed. Average telomere length is therefore only indirectly related to cellular behaviour: the shortest t","c":["longevity"],"k":"concept","x":"established","h":"present","w":1116,"e":"Human genetics ties telomerase mutations to the short telomere syndromes, and Mendelian randomization ties inherited longer telomeres to higher cancer risk; no trial has tested telomerase therapy for aging in people.","n":24},{"s":"longevity-dividend","t":"The longevity dividend","d":"The argument that slowing biological aging would produce economic gains larger than curing any individual disease, and the disputes over how that value is calculated and who would pay.","g":["economics","aging","policy","healthspan","pensions","geroscience","health spending"],"b":"The longevity dividend is the argument that a modest slowing of biological aging would yield health and economic benefits exceeding those of eliminating any single disease, and that public research funding should be reallocated accordingly. It was named in 2006 by S. Jay Olshansky, Daniel Perry, Richard Miller, and Robert Butler, who proposed that a seven-year delay in the onset of age-related decline would deliver larger population health gains than curing cancer or heart disease. It is the economic version of the Geroscience hypothesis and the main policy case the aging-research field makes. The competing-risks argument The technical core is simple and largely undisputed. Age-related diseases compete, so a person spared one dies of another. Modelling the elimination of Cancer produces a smaller gain in life expectancy than intuition suggests, because the cohort that survives it remains at high risk of cardiovascular disease, dementia, and frailty. Attacking the shared upstream process, described in the Hallmarks of aging, shifts the whole risk profile instead of removing one branch of it. Why disease-by-disease has a ceiling US cause-elimination life tables for 1999-2001 found that removing cancer as a cause of death would raise life expectancy at birth by more than three years, and removing heart disease by almost four. Those are real gains, but far smaller than the diseases","c":["society","longevity"],"k":"concept","x":"contested","h":"2030s","w":2317,"n":20},{"s":"teleportation-problem","t":"The teleportation problem","d":"A thought experiment in which a person is scanned, destroyed, and rebuilt elsewhere, used to test whether survival requires physical continuity or only psychological continuity.","g":["identity","parfit","thought experiment","survival","uploading","philosophy of mind"],"b":"The teleportation problem is a thought experiment used to isolate what survival requires. A machine records the exact state of a person's body and brain, destroys the original, transmits the information, and assembles a molecule-for-molecule duplicate at the destination. The duplicate has every memory, every disposition, and the vivid sense of having stepped in one door and out another. The question is whether the person travelled or died and was replaced. It is the sharpest available test of theories of Personal identity and continuity, and it is the exact structure of destructive Mind uploading. The thought experiment Derek Parfit gave the standard presentation. In the simple case the original is destroyed as the scan completes, so there is only ever one claimant. Most people who imagine themselves stepping into the booth report reluctance, but find it hard to say what is lost: the duplicate is physically identical, psychologically continuous, and would insist it is the same person. Parfit then introduces the branch-line case. The scanner malfunctions: it copies without destroying. The original survives on Earth with fatal cardiac damage and a few days to live, while the replica walks around on Mars. Now the original can talk to the replica by radio. Very few people are willing to say the original should be indifferent to their imminent death because the replica exists, yet t","c":["minds"],"k":"concept","x":"speculative","h":"indefinite","w":1314,"n":8},{"s":"tissue-engineering","t":"Tissue engineering","d":"The construction of living tissue from cells, scaffolds and signalling molecules, a field with approved products for skin and cartilage but no solid organ after three decades.","g":["regenerative medicine","scaffolds","biomaterials","stem cells","transplantation","cartilage"],"b":"Tissue engineering is the construction of functional living tissue by combining cells, a supporting scaffold and biochemical or mechanical signals, either in a bioreactor before implantation or inside the body afterwards. The term was fixed by a 1993 Science article by Robert Langer and Joseph Vacanti that set out the field's programme and its founding triad. Three decades later the discipline has delivered approved treatments for skin, cartilage, cornea and thymus, but none for a kidney, liver or heart. The triad The classical formulation has three components. Cells provide the biological function. Autologous cells are taken from the patient, expanded in culture and returned; they avoid rejection but take weeks to prepare and cannot be stockpiled. Allogeneic cells allow an off-the-shelf product but usually require immunosuppression or immune-privileged siting. Increasingly they are derived from Induced pluripotent stem cells, which decouples supply from donor tissue at the cost of differentiation and safety work. Scaffold provides shape, mechanical support and a surface for attachment. Early scaffolds were synthetic polyesters already approved as resorbable sutures: polyglycolic acid, polylactic acid, their copolymers, and polycaprolactone. These degrade by hydrolysis on a tunable timescale, ideally matched to the rate at which cells lay down their own matrix. Natural scaffold","c":["bodies"],"k":"technology","x":"established","h":"present","w":1308,"e":"Approved products treat burns, chronic wounds, focal knee cartilage defects, corneal burns and congenital athymia in patients; the only organ-like construct with years of human follow-up is a small bladder series.","a":"Skin substitutes, chondrocyte implantation, limbal grafts and cultured thymus tissue are approved and delivered through specialist centres; no engineered solid organ is available at any price.","r":"difficult","n":23},{"s":"transhumanism","t":"Transhumanism","d":"The intellectual and cultural movement holding that human beings can and should use technology to overcome the biological limits of the human condition.","g":["transhumanism","movements","history","enhancement","ideology","bioethics"],"b":"Transhumanism is the position that the human condition is not fixed, that its biological limits are legitimate targets of technological intervention, and that people should be free to use such interventions on themselves. It is a philosophical stance rather than a research programme, and its adherents disagree with each other about nearly everything except that premise. Its own organisations have always been small; its influence shows most clearly in the assumptions that circulate in longevity biotech, neurotechnology and artificial-intelligence circles. Precursors The word is older than the movement and older than its twentieth-century users. Dante's Paradiso coins trasumanar for the passage beyond the human, and nineteenth-century English translators rendered it as \"transhumanise\". Modern usage does not descend from that line, and the coincidence has produced a good deal of retrospective genealogy. Julian Huxley used the word in a 1957 essay to name the idea of humanity consciously fulfilling its own potential, \"man remaining man, but transcending himself\". Huxley was a biologist and a eugenicist. The movement's later critics have made much of that lineage, and its defenders point out that his meaning was cultural and educational rather than genetic. The substantive antecedents are older and mostly literary or speculative. J. B. S. Haldane's Daedalus, or Science and the Futur","c":["people","foundations"],"k":"concept","x":"established","h":"present","w":1696,"n":28},{"s":"utah-array","t":"Utah array","d":"A silicon microelectrode array of 100 needles on a 10-by-10 grid, the standard sensor for chronic single-neuron recording in human brain-computer interface research.","g":["bci","microelectrodes","neural recording","braingate","implants","neurotechnology"],"b":"Utah array is a silicon microelectrode array: a grid of sharpened needles etched from a single block of silicon and inserted into the cortex, so that each tip records the extracellular voltage near a small number of neurons. Introduced at the University of Utah around 1990, it became and remains the standard sensor for chronic single-neuron recording in humans. Nearly every major human Brain computer interface result involving individual action potentials has used one. It has changed little since. A device designed before the field had a single human participant still sets the performance benchmark against which newer designs with higher channel counts are measured. How it works The array is machined from a monolithic block of doped silicon. Dicing saws cut a grid of columns, which are then acid-etched into tapered needles on a 400-micrometre pitch, giving a device roughly four millimetres on a side with 100 electrode sites. The shanks, typically one to one and a half millimetres long, reach the cortical layers where pyramidal-cell somata are dense. Everything except the tips is insulated with parylene-C, and the exposed tips are coated with platinum or iridium oxide to lower impedance. Insertion is the difficult step. Pressed in slowly, the array dimples the cortical surface instead of penetrating it, damaging tissue and pial vessels. A pneumatic inserter fires the array in at","c":["cybernetics"],"k":"technology","x":"established","h":"present","w":1158,"e":"People with paralysis have used implanted arrays under investigational device exemptions to control cursors, robotic arms and speech decoders; some implants recorded usable signals beyond a thousand days.","a":"Not a therapy: the US clearance covers recording for up to thirty days, and every long-term implant is placed in a research study under an investigational device exemption.","r":"difficult","n":15},{"s":"uterus-transplantation","t":"Uterus transplantation","d":"A temporary transplant of a donated uterus that lets a woman without a working one carry a pregnancy, then is removed so that immunosuppression can stop.","g":["transplantation","reproduction","infertility","pregnancy","immunosuppression","ivf","surgery"],"b":"Uterus transplantation is the transfer of a donated uterus into a woman who has none, or whose own cannot carry a pregnancy, so that she can gestate and deliver a child. Almost alone among transplants, it is intended from the outset to be temporary: the graft is removed after one or two births so that lifelong immunosuppression is never required. Since the first live birth in Sweden in 2014, dozens of children have been born this way, a record that no engineered substitute for the uterus, the Artificial womb included, can claim. Who it is for The indication is absolute uterine factor infertility, in which the uterus is absent or is present but incapable of sustaining a pregnancy. The largest congenital cause is Mayer-Rokitansky-Küster-Hauser syndrome, a form of Müllerian agenesis in which the uterus and upper vagina fail to develop while the ovaries, hormones and karyotype are typically normal. It occurs in something on the order of one in 4,000 to 5,000 female births. The acquired causes are more varied: hysterectomy for postpartum haemorrhage, cervical cancer or fibroids; severe intrauterine adhesions; and radiation injury. The procedure appeals to candidates because their ovaries usually work. A woman with Müllerian agenesis produces her own oocytes, so a child gestated in a transplanted uterus is genetically hers. Of the alternatives, adoption severs that genetic link and g","c":["reproduction","bodies"],"k":"intervention","x":"emerging","h":"present","w":1748,"e":"Dozens of live births have been reported since the first in Sweden in 2014, from both living and deceased donors; graft loss and preterm delivery are common.","a":"Performed at a small number of specialist centres, largely under research protocols, rarely reimbursed, and only after the recipient has completed IVF.","r":"difficult","n":12},{"s":"virtual-cell-models","t":"Virtual cell models","d":"Computational models that simulate a cell's molecular behaviour, from complete cell cycles of minimal bacteria to learned predictions of how human cells respond to perturbation.","g":["machine learning","systems biology","simulation","computational modelling","single cell","foundation models"],"b":"Virtual cell models are computational systems that represent what happens inside a cell (DNA, RNA, proteins, regulatory networks and the processes they support) closely enough to predict its behaviour under a condition nobody has tested. Two lineages carry the name. Mechanistic whole-cell models write down every reaction and integrate them forward in time; learned models are trained on millions of measured single cells and asked to predict the next measurement. A complete whole-cell model exists for two of the simplest bacteria known. None exists for any human cell. Two traditions A mechanistic whole-cell model aims to account for every annotated gene function in an organism at once. The 2012 model of Mycoplasma genitalium split the cell into 28 submodels covering 28 processes, spanning 401 genes, 722 compounds and 1,857 reactions, and let each submodel use whatever mathematics suited it (flux balance for metabolism, stochastic simulation for transcription), with the submodels resynchronised at short time steps. The virtue is interpretability: every prediction traces back to a stated mechanism, and a wrong prediction points at a wrong parameter. The cost is that the parameters have to come from somewhere. That model needed roughly 1,800 of them, assembled from the published literature on an organism with about 525 genes. A human cell has roughly twenty thousand. Learned models ","c":["foundations","genetics"],"k":"technology","x":"experimental","h":"2030s","w":2650,"e":"Complete whole-cell models exist only for minimal bacteria; learned models of human cell lines predict part of the transcriptional response to gene silencing, and none is validated as a model of a whole human cell.","a":"Most models and datasets are public, including Recon3D, Geneformer, scGPT and Arc's State; commercial world models are proprietary and released as previews to selected academic and industry users.","r":"context","n":4},{"s":"wearable-health-sensors","t":"Wearable health sensors","d":"Consumer devices worn on the wrist or finger that continuously record pulse waveforms, movement, and skin temperature, and infer heart rhythm, sleep, and activity from them.","g":["wearables","heart rhythm","sleep","screening","consumer health","measurement"],"b":"Wearable health sensors are consumer devices worn on the wrist, finger, or torso that record optical pulse waveforms, movement, and skin temperature continuously, and infer heart rhythm, sleep, and activity from those signals. They are among the most widely deployed health-measurement devices ever made, worn by hundreds of millions of people who are mostly not patients. Almost nothing they report has been tested against a clinical outcome; the exception is detection of atrial fibrillation, which has been studied in cohorts of several hundred thousand and cleared by regulators as a notification feature rather than a diagnosis. What the sensors measure Three sensor types do most of the work. Photoplethysmography shines green light into the skin and measures how much reaches a photodiode; capillary blood volume rises and falls with each beat, so the returning signal yields interbeat intervals, and from those come heart rate, heart-rate variability, and a measure of rhythm irregularity. A triaxial accelerometer records movement, supplying step counts, fall detection, and the raw material for sleep and wake classification. Several watches add a single-lead electrocardiogram: touching the crown, a button, or the metal frame closes a circuit across the body and produces a roughly thirty-second tracing comparable to lead I of a clinical ECG. Rings use infrared light on the finger, wher","c":["longevity","cybernetics"],"k":"technology","x":"established","h":"present","w":1822,"e":"Prospective studies in hundreds of thousands of people show smartwatch algorithms can flag atrial fibrillation, and a randomized trial in older adults raised diagnosis rates; no trial has shown better clinical outcomes.","a":"Sold over the counter worldwide from roughly a hundred to several hundred dollars, some features behind subscriptions, several available only where a regulator has cleared them.","r":"reversible","n":13},{"s":"whole-brain-emulation","t":"Whole brain emulation","d":"A proposed procedure for reproducing a particular mind by scanning one brain's structure in detail, building a computational model from the scan, and running it.","g":["emulation","connectomics","simulation","consciousness","computational neuroscience","uploading"],"b":"Whole brain emulation is a proposed procedure for reproducing a particular mind on a computer: scan the structure of one specific brain at sufficient resolution, translate that scan into a computational model of its components, and run the model fast enough and faithfully enough that it produces the same behaviour the original brain would have produced. It is distinct from building an artificial mind from scratch, and distinct from simulating a generic brain: the object is a copy of this brain, retaining its memories and dispositions. No nervous system of any size has been emulated in this sense, including the 302-neuron nervous system of the nematode C. elegans, whose wiring diagram has been published since 1986. Overview The idea is usually presented as an engineering problem rather than a scientific one. Its proponents argue that no new physics is required, only the extension of three existing capabilities: volume microscopy, computational neuroscience, and computing hardware. That framing carries a substantive assumption: that there exists some level of biological description below which further detail can be replaced by statistical noise without changing the emulated system's behaviour. The assumption is called scale separation, and whether it holds for brains is unresolved. A human brain contains roughly 86 billion neurons and a comparable number of non-neuronal cells, wi","c":["minds","foundations"],"k":"concept","x":"speculative","h":"2050s+","w":1849,"n":38},{"s":"xenobots","t":"Xenobots","d":"Sub-millimetre motile constructs assembled from frog embryonic cells and shaped by an evolutionary algorithm, classed as neither robots nor organisms in any settled sense.","g":["synthetic biology","morphogenesis","biorobotics","regeneration","self-assembly","michael levin"],"b":"Xenobots are motile constructs, under a millimetre across, made by sculpting clumps of embryonic cells from the African clawed frog Xenopus laevis into shapes selected by an evolutionary algorithm running in a physics simulator. They carry no engineered hardware, no circuitry and no edited DNA. They move by beating cilia or by contracting embryonic heart muscle, and they run on yolk the cells carried out of the egg. The first were reported in 2020 by Sam Kriegman, Douglas Blackiston, Michael Levin and Josh Bongard, working between Tufts University and the University of Vermont. The name joins the genus Xenopus to the back half of robot, and that second half accounts for most of the misunderstanding since. How they are made The process has two stages that do not interact. In the first, an evolutionary algorithm searches a space of soft-body designs built from voxels of two kinds, passive tissue and contractile tissue. It scores each candidate in simulation on a task such as travelling in a straight line or pushing a particle, then filters the survivors for robustness, since a design that collapses under small perturbations will not survive transfer to tissue. In the second stage a person builds the winning shape by hand. Animal cap tissue is dissected from blastula-stage frog embryos, dissociated, and left to reaggregate into a coherent ball. Microsurgical forceps and a cautery ","c":["bodies"],"k":"technology","x":"experimental","h":"2040s","w":1687,"e":"No xenobot has been placed in an animal or a person; the human-cell version, anthrobots, has been tested only in culture dishes, including on sheets of cultured human neurons.","a":"Not a product. Built in a small number of academic laboratories from frog embryos or donor-derived human airway cells; none are sold, licensed, or approved for any use.","r":"reversible","n":5},{"s":"xenotransplantation","t":"Xenotransplantation","d":"The transplantation of organs between species, now pursued with genetically engineered pigs whose antigens and clotting proteins have been altered to survive in a human recipient.","g":["transplantation","organ shortage","genome editing","immunology","pigs","clinical trials"],"b":"Xenotransplantation is the transplantation of living cells, tissues or organs between species. In its modern form it means moving a genetically engineered pig organ into a human, using edits that remove the sugars human antibodies attack and add human proteins that control complement activation and blood clotting. Between 2021 and 2025 the field moved from brain-dead research recipients to living patients under compassionate-use authorisation, and then to formally cleared clinical trials. Every graft so far has failed or been removed within months. Why pigs The driver is arithmetic. More than a hundred thousand people are on the United States transplant waiting list at any time, the great majority waiting for a kidney, and the US Health Resources and Services Administration puts the number dying each day while waiting at around seventeen. Waiting lists understate demand, because patients too sick or too old to qualify are never listed. The structural causes are set out in Organ shortage, and no combination of donation reform, mechanical support and improved organ preservation closes the gap. Non-human primates are immunologically closer, but they breed slowly, are expensive and ethically fraught, and carry viruses that cross to humans readily. Pigs breed fast, reach human organ size in months, tolerate genetic modification, and are already farmed at scale. Their organs are anat","c":["bodies","genetics"],"k":"technology","x":"experimental","h":"2030s","w":1260,"e":"Two patients received gene-edited pig hearts and several others pig kidneys under compassionate use; every graft has failed or been removed within months, and formal kidney trials were cleared in 2025.","a":"No marketed product and no price: recipients so far have been patients ineligible for a human organ, treated under compassionate-use authorisation, with the first kidney trials cleared in 2025.","r":"difficult","n":18},{"s":"xprize-healthspan","t":"XPRIZE Healthspan","d":"A $101 million incentive competition launched in 2023 that rewards a therapy restoring at least a decade of muscle, cognitive and immune function in older adults.","g":["healthspan","prizes","clinical trials","aging","functional endpoints","geroscience"],"b":"XPRIZE Healthspan is a seven-year, $101 million incentive competition launched in November 2023 that offers its grand prize to a team demonstrating a therapy that restores at least a decade of function in three domains (muscle, cognition and immunity) in adults aged 50 to 80, using a treatment course of no more than a year. For the field, the endpoint matters more than the money: the competition is the most detailed public attempt to define what a successful Healthspan intervention would have to show. Overview Incentive prizes are used where a goal is well defined, a solution is plausible, and no market pays for the intermediate steps. The XPRIZE Foundation, which ran the Ansari prize for suborbital spaceflight and later competitions in genomics and carbon removal, applies the model by specifying an outcome and letting teams choose the route. The Healthspan competition is designed around a specific problem. No regulator recognizes aging as an indication, so no company can run a registrational trial against it, and the field has no qualified surrogate endpoint that would let a shorter trial substitute for decades of follow-up. The prize sidesteps both obstacles by scoring measured function rather than mortality or biomarkers. If a 70-year-old performs across three domains as a 60-year-old would, the intervention has restored ten years of function by the competition's definition,","c":["organizations","longevity"],"k":"organization","x":"emerging","h":"late 2020s","w":1190,"n":20},{"s":"yamanaka-factors","t":"Yamanaka factors","d":"The four transcription factors Oct4, Sox2, Klf4 and c-Myc, which together convert a differentiated cell into an induced pluripotent stem cell.","g":["reprogramming","stem cells","transcription factors","epigenetics","pluripotency"],"b":"Yamanaka factors are the four transcription factors, Oct4, Sox2, Klf4 and c-Myc, whose forced expression converts an ordinary differentiated cell into a pluripotent stem cell. Their identification in 2006 collapsed a problem that had required eggs, embryos and nuclear transfer into a defined set of four genes that any laboratory could introduce into skin cells. The same four are now the starting point for Epigenetic reprogramming as a rejuvenation strategy, where the goal is to apply them briefly enough that the cell is reset without being converted. What each factor does Oct4, encoded by POU5F1, is the core pluripotency regulator; it is expressed in the early embryo and in embryonic stem cells, and no reprogramming cocktail has reliably dispensed with it or a close functional substitute. Sox2 binds cooperatively with Oct4 at composite motifs and helps activate the pluripotency network. Klf4 supports self-renewal, suppresses apoptosis in cells being pushed out of their identity, and cooperates with the other two at enhancers. c-Myc is not a pluripotency factor at all: it is a broadly acting driver of proliferation and chromatin opening, and it raises reprogramming efficiency largely by making the genome more permissive. Two of the four, Klf4 and c-Myc, are proto-oncogenes. That shapes the work downstream: tumours appeared in early chimeric mice, and every proposed therapeutic u","c":["genetics","longevity"],"k":"technology","x":"established","h":"present","w":1228,"e":"Human cells have been reprogrammed to iPSCs since 2007 and clinical-grade lines are made routinely; no partial-reprogramming therapy using these factors has entered human testing with published results.","a":"A research reagent: the factors are used daily in laboratories and in clinical-grade iPSC manufacturing, and are not available as a treatment in any country.","r":"irreversible","n":16}]}