In brief

Anthropic said on September 23 that Claude agents, searching huge DNA databases, spotted an overlooked enzyme system in viruses that infect bacteria. It has evenly spaced repeats like those in CRISPR. Anthropic’s own lab made a first test, but the work is not peer-reviewed.

New to this? Read it in simple words
  • Anthropic says its AI, Claude, found an overlooked group of genes in viruses that infect bacteria.
  • The genes sit next to repeated pieces of DNA, a pattern that looks like CRISPR.
  • Anthropic’s own lab did a first test. No outside scientists have checked the work yet.
  • Nobody knows yet what the system does, or if it will ever be useful.
Words to know
CRISPR
A natural defence system in bacteria that scientists turned into a tool for editing genes.
Enzyme
A protein that speeds up a chemical reaction in a living thing.
Peer review
When independent experts check a study before a journal publishes it.

What Claude found

ART stands for array-associated reverse transcriptases. It has three parts: an enzyme that copies RNA into DNA, a partner gene with an unknown role, and a row of evenly spaced DNA repeats.

Those spaced repeats look like the arrays in CRISPR, the bacterial defence system behind today’s best-known gene-editing tools. The resemblance is in the layout. Anthropic has not shown that ART cuts or edits DNA.

The enzyme itself was already known from earlier studies of a large phage. Anthropic says Claude was the first to notice the repeat array and the partner protein next to it.

Chief executive Dario Amodei wrote on X that a Stanford team had earlier found a system that is similar in some ways.

Sources134

LAB CLAIM 02
Claude spotted the pattern. What the system does is still unknown.

All lab results so far come from Anthropic’s own lab. The preprint is not peer-reviewed.

How the search worked

Anthropic says about 950 Claude agents searched for 21 hours and used around 210 million tokens. They screened more than 200,000 enzymes, narrowed them to 3,500 candidates, and wrote 20 reports for scientists.

According to the preprint, as reported by The Next Web, the agents ran on Claude Mythos 5. When Anthropic repeated the same search ten more times, every rerun missed the repeat array.

People wrote the first instructions, reviewed the reports, chose what to test, and did all the lab work. Claude searched the data, picked candidates, wrote the reports, and helped interpret the results.

Anthropic’s own scientists ran the first test in its Bay Area lab. They found that the repeat array is turned into distinct short RNAs. No outside lab has tested the system yet.

Sources146

Not a CRISPR rival yet

The work has not been peer-reviewed. The preprint is posted only on Anthropic’s website, and no data or code has been released.

What ART does in nature is unknown. So is whether its enzyme is active, and whether it could ever become a useful tool.

Stanford bioengineer Stanley Qi told Al Jazeera the finding is very exciting. Microbiologist Kevin Blake of Washington University School of Medicine was more careful: “There’s nothing to indicate this is a rival to CRISPR-the-technology”.

Some early reports described ART as a new gene-editing tool. Amodei wrote only that Anthropic suspects this, and that the system’s function and importance are not yet clear.

Anthropic says its lab works only at biosafety levels 1 and 2 and handles no human pathogens.

Sources1235

Sources

Every fact in this story comes from the sources below. Open them to check our work.

  1. 1
    Primary source · September 23, 2026Claude discovers a novel enzyme system with CRISPR-like repeats Anthropic
  2. 2
    Research · September 23, 2026Anthropic says Claude AI helped discover novel enzyme system Reuters via KSL
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How we checked this story

We read Anthropic’s announcement, then compared Reuters, TechCrunch, The Next Web, and Al Jazeera. We could not open the full preprint, so details from it come from The Next Web’s reporting. All lab results are Anthropic’s own, and no outside lab has repeated them.