Common genetic variants that have minor effects may contribute about half the risk of developing autism, according to a study published Sunday in Nature Genetics. Identifying these variants would require tens of thousands of samples.

The number of people in a study, the proportion of male and female participants, and many other factors can affect research on sex differences in autism, says Thomas Frazier.

Proteins that help guide neurons to their correct destination in the brain may be involved in autism, says Christopher Cowan.

Untrained volunteers can reliably detect signs of autism in children by watching home videos of the children posted on YouTube, suggests a study published 16 April in PLoS One. But critics say fundamental design flaws in the study undermine its results.

Mutations in a gene associated with DNA packaging may lead to autism and intellectual disability, suggests a study published 16 February in Nature Genetics.

Two studies published in the past month lend support to the notion that autism looks different in girls than it does in boys, making it harder to recognize and diagnose in girls. The studies reflect growing suspicion in the research community that the underlying biology and the experiences of girls with autism may both be distinct.

It takes more mutations to trigger autism in women than in men, which may explain why men are four times more likely to have the disorder, according to a study published 26 February in the American Journal of Human Genetics.

In families with a history of autism, the affected children are seven times more likely to also have epilepsy than their unaffected siblings, according to a study published 1 December in Molecular Autism. The results suggest that epilepsy and autism share some risk factors.

Mutations in TRIM33, a protein that is part of the cell’s cleanup crew, may up the risk for autism, according to a study published 5 November in Molecular Psychiatry.

A large new project aims to link specialized psychiatric units across the U.S. to investigate the causes and best treatment for autism’s most severe and challenging cases.