A Claude model autonomously chose a gene therapy and operated on a mouse brain with no human decision-making

An AI agent chose a drug, target region, and coordinates for surgery on a mouse model of epilepsy, then performed the procedure. Midway through, it refused to bypass a safety restriction. The team gave Claude Sonnet 5 a list of 19 possible gene therapies, an epilepsy mouse model in which researchers induce seizures to test treatments, and access to a custom motorized surgical device with cameras.

Its only instruction was to reduce the mouse's seizures. The agent selected the drug, brain region, and stereotactic coordinates on its own, according to Gabriel Ocana-Santero, Exin Therapeutics cofounder and CEO and a PhD student at the University of Oxford. He described the procedure in a thread on X. The agent first analyzed how seizures arise in this particular model, then proposed a therapy that boosts a specific inhibitory signaling pathway in the brain.

It picked a brain structure that the scientific literature identifies as the origin point for this type of seizure. It rejected a second possible target region with a detailed explanation, arguing that the region's effects were too unreliable and had…