The Oxford Physician Who Edited the First Human Genome Is Now Learning to Write New Ones

Adrian Woolfson oversaw the first clinical trial to edit a living person’s DNA. With his new book and the company he cofounded, he is arguing that medicine’s next act is not editing genomes but writing them from scratch.

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In November 2017, in an infusion center in Oakland, California, a 44 year old man named Brian Madeux became the first human being in history to have his genome edited inside his own body. The therapy, developed by Sangamo Therapeutics, used zinc finger nucleases delivered by a viral vector to insert a working copy of a gene into a precise address on chromosome 19. Madeux had a rare metabolic disease called Hunter syndrome, a condition that slowly destroys tissue because the body cannot break down certain complex sugars. The edit was an attempt to give him, for the first time in his life, a liver that could make the missing enzyme. The procedure itself took less than three hours. The implications of it have not stopped unfolding since.

The Executive Vice President and Head of Research and Development who ran the program that made the Madeux trial possible was a British physician named Adrian Woolfson. By the time that infusion bag was hung, Woolfson had already lived three careers in one. He had trained as a physician at Balliol College, Oxford. He had earned his doctorate at the MRC Laboratory of Molecular Biology in Cambridge under the Nobel laureate César Milstein, the biologist who invented monoclonal antibodies and effectively made modern immunotherapy possible. He had run global oncology medical leadership at Bristol Myers Squibb in Princeton, led early and late stage immuno oncology at Pfizer in New York, and served as Chief Medical Officer of a Swiss biotech developing personalized cancer vaccines. At Sangamo, he oversaw a portfolio of gene editing, cell therapy, and transcriptional regulation programs, including the program that eventually became the first in human genome edit.

That is a biography with an obvious question attached to it. Why, given that résumé, would someone leave the established center of pharmaceutical medicine to build a company whose premise is that the current frontier of gene editing is, in his own framing, the beginning rather than the destination?

From reading DNA to writing it

Woolfson’s argument, distilled, is that medicine has spent seventy years learning to read the genome and is now on the threshold of learning to write it. The distinction matters more than it sounds. Reading, in this context, means sequencing: the ability, pioneered by Frederick Sanger in 1977, to determine the exact order of nucleotides in any strand of DNA. Editing, the capability that CRISPR and zinc finger nucleases unlocked, means changing a small number of those nucleotides in place. Writing means something more ambitious. It means designing a genome on a computer, then synthesizing the physical DNA to match that design, and inserting the result into a cell to see whether it produces a viable organism.

For most of molecular biology’s history, writing at any useful scale was impossible. In 1955, the British biochemist Alexander Todd and his colleague A. M. Michelson managed to chemically synthesize an artificial DNA fragment two nucleotides long. A complete human genome contains roughly three billion nucleotide pairs. Closing that gap has been the quiet project of a small community of synthetic biologists for most of the intervening seven decades.

In 2019, a team led by Jason Chin at the MRC Laboratory of Molecular Biology in Cambridge, the same institution where Woolfson had trained, published one of the field’s most important results to date. Working with a laboratory strain of E. coli, they constructed a synthetic bacterial genome that used only 61 of the genetic code’s 64 codons, rather than the usual 64. The organism, called Syn61, was reported in Nature. It was the largest synthetic genome ever built at the time, and the first to demonstrate that the fundamental grammar of the genetic code was negotiable. One of the co first authors on that paper was Kaihang Wang, a molecular biologist then at the MRC LMB. Wang is now one of Woolfson’s cofounders at Genyro.

The ensemble at Genyro

Genyro, founded in October 2024 and headquartered in San Diego, was built on a thesis that sounds simpler than it is. The company’s premise is that three distinct technologies, each developed independently over the last decade, have reached maturity at roughly the same moment, and that combining them produces something new. The first is artificial intelligence, specifically the generation of AI foundation models trained on biological sequence data. The second is high throughput DNA synthesis, the ability to construct long strands of DNA from scratch at commercial scale. The third is genome assembly, the set of laboratory techniques that take synthesized DNA fragments and stitch them into complete, functional chromosomes inside living cells.

Woolfson’s cofounders map onto each of those layers. Brian Hie, an Assistant Professor of Chemical Engineering at Stanford and an Innovation Investigator at the Arc Institute, leads the AI side. In March 2026, Hie and Patrick Hsu at the Arc Institute, along with colleagues at NVIDIA, Stanford, and UC Berkeley, published Evo 2 in Nature, a biological foundation model trained on 9.3 trillion DNA base pairs spanning all domains of life. The model can predict the functional consequences of mutations it has never seen, including clinically significant BRCA1 variants, and can generate plausible genome sequences at scale. It is, in effect, a large language model for biology, where the language is DNA.

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Kaihang Wang, now a tenure track Assistant Professor of Biology and Biological Engineering at Caltech, runs the synthesis side. In January 2026, Wang and his colleagues published the Sidewinder DNA construction technology in Nature. Sidewinder introduces a three way DNA junction that separates the information guiding assembly from the final assembled sequence, reducing the misconnection rate from roughly one in ten or one in thirty using conventional methods to approximately one in a million. If Evo 2 is the design software, Sidewinder is the printer. Genyro has entered into an exclusive licensing agreement with Caltech for the technology. Noah Robinson, the Sidewinder paper’s first author, is Genyro’s Chief Technology Officer. The scientific advisory board includes the Nobel laureates Frances Arnold and Roger Kornberg, the Moderna cofounder Bob Langer, and Jason Chin, the Cambridge biologist who led the Syn61 project and now directs the Oxford Generative Biology Institute.

Woolfson, in turn, brings the translation layer between the laboratory and the clinic. He is the Genyro cofounder who has actually run first in human trials of genome editing in oncology, who has sat across the table from regulators, and who has built and run global medical affairs organizations inside the world’s largest pharmaceutical companies. Before Genyro, he founded and led Replay, an earlier genome writing company. His peer reviewed 2025 paper in Molecular Therapy, titled “ABI and generative biology: a new paradigm for gene therapy, genome engineering, and engineered cell therapy,” outlines the clinical case for the approach. The thesis is that Artificial Biological Intelligence, as he calls it, will compress the timelines, reduce the costs, and widen the target space of next generation therapeutics, particularly for the categories of disease where current gene therapy has struggled to deliver.

The book, and the argument

In February 2026, Bloomsbury and MIT Press published Woolfson’s third book, On the Future of Species: Authoring Life by Means of Artificial Biological Intelligence. It is available at major retailers. The book is, on its surface, a technical survey of where genome writing currently stands and where it appears to be heading. Underneath that, it is something stranger and more interesting. It is a meditation on what it would actually mean for humans to have the ability to design life.

Woolfson borrows a metaphor for this from the Argentinian writer Jorge Luis Borges. In his 1941 story “The Library of Babel,” Borges imagined a library of indefinite, and perhaps infinite, size, containing every possible book that could be written using 25 alphabetic characters. Most of the books in the library are nonsense. The meaningful ones, the novels and histories and biographies, are scattered across its infinite expanses like rare islands in an endless sea of gibberish.

The metaphor translates almost directly to biology. The four nucleotide bases of DNA generate a similar combinatorial library, one in which every possible genome sequence has a defined address. The philosopher Daniel Dennett called this the Library of Mendel. Woolfson prefers to call it Fred’s Library, in honor of Sanger, the biochemist who gave us the ability to read any entry in it. Nature, through Darwinian evolution, has explored a vanishingly small corner of this space over four billion years. Humans, through selective breeding, have nudged the exploration a little further. Genyro and its peer companies are trying to build the first navigation system capable of charting the rest of it.

The stakes, on Woolfson’s telling, are not modest. If the library is mostly charted, humans acquire an unprecedented capacity to design organisms, proteins, and therapeutics. Diseases of genetic origin become addressable at their source. Species lost to extinction become, in principle, recoverable. The boundaries of human health and human lifespan become engineering questions rather than biological ones. Woolfson is clear that this capacity also carries risks serious enough to warrant a formal moral and regulatory framework, and the closing chapters of the book are devoted to sketching one.

His earlier books, Life Without Genes (HarperCollins, 2000) and An Intelligent Person’s Guide to Genetics (Duckworth, 2006), are both worth reading as the intellectual scaffolding for the new argument. The first traces the history of the genome as a concept. The second explains, for an intelligent general audience, how the machinery of inheritance actually works. Together with On the Future of Species, they form a three volume arc that tracks the field from its discovery to its current inflection point.

Why this belongs in HealthcareDiscovery.ai’s library

Most consumer health conversations, even the ones carried out at high quality, stop at the level of behavior. Eat this, move this way, sleep this many hours. The foundational practices matter enormously, and the bulk of what any individual can control over the next five years sits inside those five categories. But the reason those practices matter at all, on the longer horizon, is that staying healthy now is the bridge to whatever is coming in the laboratory next.

Woolfson’s work is a useful test case for thinking about what coming means. The Sangamo trial that edited Brian Madeux’s genome was, at the time, a nearly unimaginable procedure. Eight years later, CRISPR therapies for sickle cell disease have FDA approval, two genome foundation models have been published in Nature, and a San Diego company whose cofounders include the senior author of Sidewinder, a senior author of Evo 2, and the physician who oversaw the first in human genome edit has launched with exclusive rights to one of the most important DNA construction technologies ever published. The timeline between science fiction and infusion pump is collapsing in a way that was not visible to most observers a decade ago.

Featured Voices, a new HealthcareDiscovery.ai series, will profile the people who are quietly shaping that collapse. The goal is not celebrity coverage. It is to surface the thinkers whose work, read seriously and followed over time, gives a general reader a defensible map of where healthcare is actually heading. Woolfson is the first entry in the series because he sits at the exact intersection the site is built to cover: practicing physician, laboratory scientist, industry leader, and author, all at once.

What this means for you

There is an honest answer to the question of what to do with all of this, and it sounds less exotic than the research that produced it. The work of genome writing will unfold on timelines measured in years rather than months. The therapies that emerge from Genyro and its peers, if they work as their founders believe they can, will reach the clinic over the back half of this decade and through the 2030s. Almost none of those therapies will be available to healthy adults as consumer products. They will be prescribed, in clinical settings, for specific conditions, under medical supervision.

The most consequential thing you can do in the meantime is remain eligible for what is coming. The research thesis popularized by Ray Kurzweil as Longevity Escape Velocity makes this explicit. If you extend your healthy life by one year for every year that passes, you bridge yourself to the next wave of medical breakthroughs. The five foundational pillars of nutrition, sleep, movement, breathwork, and mindset are not in competition with what Woolfson is building in San Diego. They are the mechanism by which you stay in good enough shape to benefit from it when it arrives.

The four categories of chronic disease that drive most premature mortality in developed countries, cardiovascular disease, cancer, neurodegenerative disease, and metabolic dysfunction, are precisely the categories that AI designed and synthetically written therapeutics are being pointed at. The convergence is not accidental. Serious wellness and serious medicine are closing in on the same targets from opposite directions. One wave is being built in laboratories in San Diego and Cambridge and Palo Alto. The other is available to you tonight, at the dinner table, in the gym, and in the hour before you go to bed.

Adrian Woolfson is one of the people building the first wave. The second is up to you.

Explore more in the HealthcareDiscovery.ai library, including the foundational science behind the Five Pillars and the Four Shadows framework for chronic disease.

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