Anthropic says Claude spent about 21 hours and roughly 210 million tokens scanning DNA databases before identifying an unusual enzyme system now known as ART.
CRISPR pioneer Feng Zhang reviewed the preprint and described the discovery as “genuinely intriguing.”
Anthropic chief executive Dario Amodei said the system’s “precise function, biotechnological utility (if any), or level of significance is not yet clear.”
Anthropic said in a Wednesday release that Claude had identified a new molecular system in viral DNA. In the same announcement, Amodei cautioned that its “precise function, biotechnological utility (if any), or level of significance is not yet clear.”
In practical terms, Claude has found a biological signal, but researchers have not yet determined what it does, whether it can be used biotechnologically or how important the discovery is.
Anthropic publicized the finding despite those unresolved questions.
The system was discovered in bacteriophages—viruses that infect bacteria—beside a repetitive DNA region resembling a CRISPR array, the bacterial defense mechanism that inspired modern gene-editing technologies. Anthropic named the discovery ART, short for array-associated reverse transcriptases.
Reverse transcriptases are enzymes that copy RNA into DNA, a capability used by some viruses and bacteria. Claude examined more than 200,000 reverse transcriptases, narrowed the search to 3,500 unusual candidates and then selected 20 for closer study.
The search took about 21 hours, involved roughly 950 AI agents working in parallel and used approximately 210 million tokens—the units of text an AI model processes as it reasons.
“At minimum it is work I would have been proud to do as a PhD student,” Amodei said. Some observers have questioned whether identifying an unexplained system should be presented as a major scientific achievement before its function and significance are established.
The sad thing is that Dario knows better.
He was a PhD student. He knows the significance level of this result. He knows that if he had walked into Bill’s office (his advisor) with “we found an interesting system, but we still don’t know what it does” and said he was ready to…
— Ravid Shwartz Ziv (@ziv_ravid) September 23, 2026
In plain English: what this was, and whether it was “bad.”You pointed at a tweet by Min Choi. That tweet was hyping an Anthropic announcement: their AI, Claude, helped spot a weird stretch of DNA in bacteriophages (viruses that infect bacteria). Next to a known kind of enzyme sat…
— Tyler Lockton (@Tlockty) September 23, 2026
The reaction has not been entirely critical. Anthropic also received support from researchers and observers who see potential value in the discovery process.
According to Anthropic’s release, Zhang, a CRISPR pioneer affiliated with MIT and the Broad Institute, reviewed the preprint and called the work “genuinely intriguing.” He added: “This is an exciting example of how AI agents can contribute to biological discovery.”
“The discovery itself is fascinating, but the process may be even more important. Claude did not perform the laboratory experiments (though it probably soon could),” Owen Lewis of the Techno-Optimist substack wrote. “Human scientists reviewed its hypotheses, selected the most promising candidates, and carried out all of the wet lab work.”
Well that didn’t take long. p(abundance) is increasing.
Anthropic has published the first result from its new molecular biology (wet) lab, where its scientists are using Claude to explore large biological datasets, search the scientific literature, generate hypotheses, and…
— Owen Lewis (@is_OwenLewis) September 23, 2026
If ART proves useful, its path to any clinical application would likely take years. Anthropic has not suggested a shorter timeline.
The market reacted quickly. Shares in gene-editing companies including CRISPR Therapeutics, Intellia Therapeutics and Beam Therapeutics declined after the announcement.
This is not the first Anthropic result that required substantial qualification. In July, the company said Claude Mythos had solved a post-quantum cryptography problem that had challenged researchers for years.
That result ultimately withstood extensive human verification, although it concerned a signature scheme and a reduced-round cipher variant that had never been deployed. The new biological finding may follow a similar path: a genuine discovery with major unresolved questions.
What is confirmed at this stage is an unusual protein pattern, one outside expert describing it as “intriguing” and no timetable for determining whether it has scientific or practical value. Anthropic says laboratory work is already underway.
