OpenAI's o3 Reanalyzes 376 Unsolved Rare Disease Cases, Yielding 18 New Diagnoses

A joint study by Boston Children's Hospital, Harvard University and OpenAI reanalyzed 376 previously unsolved pediatric rare genetic disease cases using OpenAI's reasoning model "o3 Deep Research," leading to 18 new confirmed diagnoses, according to a paper published in NEJM AI on June 18, 2026. Led by Boston Children's Hospital's Manton Center for Orphan Disease Research, the paper is titled "LLM-Assisted Reanalysis of Unsolved Rare Disease Genomes Increases Diagnostic Yield." The additional diagnostic yield was 4.8%.