Both premature and post-term babies develop more severe symptoms of autism than those born close to their due dates, according to a study published 16 March in the Journal of Autism and Developmental Disorders.

Full siblings are twice as likely as half siblings to share a diagnosis of autism, according to a short report published 28 February in Molecular Psychiatry. The results suggest that genetic factors play an important role in the risk of developing autism, the researchers say.

Molecules generated by an immune reaction in pregnant rats affect the brains of their offspring, leading to changes in gene expression, according to a study published 30 January in Brain, Behavior and Immunity.

Scientists worry that funding cuts to the National Children’s Study, an ambitious effort to track 100,000 children in the United States from before birth through age 21, may harm recruitment efforts.

Immigrating to another country during pregnancy appears to boost the risk of having a child who has low-functioning autism, according to a comprehensive, population-based study in Sweden. The research was published online 23 February in the British Journal of Psychiatry.

A commonly used flame retardant may lead to deficits in sociability, learning and memory in healthy female mice and those that model Rett syndrome, according to a study published 15 February in Human Molecular Genetics. The effects are different in Rett syndrome models compared with healthy mice, suggesting gene-environment interactions.

Maternal antibodies that attack fetal brain proteins could underlie some cases of autism, says immunologist Betty Diamond.

A new study claims that low folate levels contribute to autism and offers a tenuous explanation for the low levels.

When twins differ in their diagnosis of autism, the twin with the lower birth weight is about three times more likely to develop the disorder than his or her sibling, according to a study published in the December issue of Psychological Medicine.

Research on the immune system’s link to autism and other psychiatric disorders is rich and varied — from massive epidemiological studies of twins and pregnant women, to the screening of immune molecules in amniotic fluid and postmortem studies of brain inflammation. In his new book, Paul Patterson lays out this complicated work clearly and concisely, with little editorializing.