Individuals with either of two rare forms of epilepsy have duplications or deletions that encompass genes implicated in autism and language impairment, according to a study published 27 June in Epilepsia.

Genes and the environment each influence the role of the other in determining the risk of developing autism. Genetics can determine how susceptible one is to the environment, and environmental factors can influence gene expression and introduce mutations, says immunologist Janine LaSalle.

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.

Analyzing how mutations in people with autism affect gene expression in blood-derived cells could help researchers pinpoint harmful mutations, according to research published 21 July in The American Journal of Human Genetics.

The absence of a chemical alteration called methylation on some stretches of DNA makes them especially prone to mutations, according to a paper published in PLoS Genetics in May.

Deletions in the second half of the autism-linked gene neurexin-1 are associated with seizures and large head size, according to a study published 23 May in the European Journal of Human Genetics.

To find the pathogenic mutations in complex disorders such as autism, researchers may need to conduct sophisticated analyses of the genetic functions that are disrupted, says geneticist Aravinda Chakravarti.

An analysis of large duplications and deletions of DNA has identified new candidate genes for autism in pathways linked to the disorder. The results were published 22 May in Human Molecular Genetics.

By screening for recessive mutations, which are present in both copies of a gene, researchers have identified four autism candidates that may be involved in neuronal signaling, according to a study published 12 April in PLoS Genetics.

Large-scale swapping of genetic material between chromosomes may play an important role in autism, according to a study published 27 April in Cell.