A rare childhood speech disorder related to social anxiety is associated with a gene linked to autism, according to a study published in December in Biological Psychiatry. The results suggest that the two disorders share a common mechanism.

Researchers have identified a rare genetic variant linked to autism in DLX1, a gene that regulates the growth of neurons, they reported in December in the American Journal of Medical Genetics.

High levels of serotonin in the womb may up the risk of autism in the child, according to a study published in December in the American Journal of Medical Genetics.

The pattern of interactions among different genes in yeast cells changes in response to disease-like conditions, in this case a DNA-damaging agent, according to a study published 3 December in Science. Mapping epistasis — how various cellular factors work together — is key to understanding complex disorders, such as autism.

A variant of the autism risk gene CNTNAP2 may alter the brain to emphasize connections between nearby regions and diminish those between more distant ones, according to a study published 3 November in Science Translational Medicine.

Areas of the brain that are active when people are daydreaming or sleeping, and quiet when they are engaged in a task, are imperfectly synchronized in people with autism and attention deficit hyperactivity disorder, researchers say.

A common variation within a region on chromosome 16 puts a large proportion of the general population at risk for intellectual disability, according to a study published in August in Nature Genetics.

One of the largest genome-wide association studies for autism spectrum disorders, reported last week in Human Molecular Genetics, allows only one definitive conclusion: it isn’t large enough.

Researchers have pinpointed the brain circuits that underlie the vasopressin hormone’s role in regulating emotions.

Several independent groups have found previously unknown risk genes for autism, schizophrenia and mental retardation. The candidate genes have one thing in common: they encode proteins that are needed for the healthy function of synapses, the junctions between neurons.