After doubling its sample size, the largest study of genetic data from autistic people has identified 255 genes associated with the condition, an increase of more than 40 genes since the researchers’ 2019 update; 71 of the genes rise above a stringent statistical bar the team had not previously used. The new analysis also adds data from people with developmental delay or schizophrenia and considers multiple types of mutations.

“It’s a really significant step forward in what we do,” said Kyle Satterstrom, a computational biologist in Mark Daly’s lab at the Broad Institute in Cambridge, Massachusetts. Satterstrom presented the findings virtually on Tuesday at the 2021 International Society for Autism Research annual meeting. (Links to abstracts may work only for registered conference attendees.)

The team’s previous analyses used data from the Autism Sequencing Consortium, which enrolls families through their doctors. The researchers mainly scoured the genetic data to find rare, non-inherited mutations linked to autism.