A complicated interplay between a certain genetic variant and autism, schizophrenia and rheumatoid arthritis adds one more intriguing correlation to the growing list of autism risk factors.

Genetic variants in two autism-associated genes have been linked to repetitive behavior and hyperactivity, two common symptoms of the disorder, according to two studies published in the past few months.

By zapping mouse brains with blue and yellow light beams, scientists have manipulated the animals’ social behaviors and bolstered a popular theory of what causes autism.

The first study to sequence more than 100 genes on the X chromosome in people with autism or schizophrenia has turned up some promising leads.

A variant of neurexin 1, a gene linked to both autism and schizophrenia, is associated with less brain matter than normal in healthy individuals, according to a study published 8 June in PLoS ONE.

Small fragments of RNA, called microRNAs, can fine-tune the levels of proteins at the junctions between neurons in response to cell signals, according to a study published 10 June in Molecular Cell.

Mice lacking SHANK1, a member of a family of autism-associated proteins, communicate less with their mothers and potential mates than controls do, according to a study published 9 June in PLoS One.

Individuals with autism do not have so-called ‘eagle-eyed’ vision as reported by some studies, according to research published 10 June in the Journal of Autism and Developmental Disorders.

A new study of twins proposes the controversial claim that environmental influences during early development are just as, if not more, important than genetics. But the findings are not substantially different from those of previous twin studies, however, and some experts are critical of the study’s statistics.

Blood cells from individuals who have autism produce less-than-normal amounts of SHANK3 and NLGN3 proteins, according to a study published 26 May in Molecular Autism.