An autism-linked mutation in the signaling protein EPAC2 alters the shape of neuronal branches, according to a study published in the June issue of PLoS Biology.

Abnormalities in the connections between language-related brain regions are similar in people with autism and those with tuberous sclerosis, a genetic disorder characterized by benign tumors throughout the brain and body, according to a paper published 1 June in Cerebral Cortex.

Mutations in two genes linked to autism, neurexin and neuroligin, slow down neuronal signaling, according to research published 2 August in Science. Analyzing the mutations in the nematode Caenorhabditis elegans, the study found that mutations in these genes affect signaling in the opposite direction than is typical.

The autism-associated gene RBFOX1 modifies the sequence of hundreds of genetic messages, a number of which affect the expression of other autism-linked genes, according to a study published 7 July in Human Molecular Genetics.

Several lines of converging evidence suggest that low-density lipoprotein receptor-related protein 2 (LRP2), which is involved in early patterning of the brain, is a risk gene for autism.

The presence of any of three abnormal physical features — an asymmetrical face, tufts of hair growing in the wrong direction or a prominent forehead — can help diagnose autism, according to a study published 6 June in the Journal of Autism and Developmental Disorders.

TAOK2, a gene in the autism-associated 16p11.2 chromosomal region, is part of a signaling pathway that builds neuronal connections during development, according to a study published 10 June in Nature Neuroscience.

Motor neurons derived from individuals with Phelan-McDermid syndrome, a rare autism-related disorder, form abnormal connections with muscle cells. The unpublished research was presented 26 July at a meeting of the Phelan-McDermid Syndrome Foundation in Orlando.

Some studies have suggested that people with autism have deficits in executive function — a set of complex mental processes involved in everyday life. But these results may instead reflect their difficulties imagining what other people are thinking, according to a provocative new hypothesis.

Women who have a milder version of the fragile X mutation, which can lead to the full mutation in their children, have some features of autism, according to a study published 12 June in the American Journal of Medical Genetics.