Individuals who have autism or another psychiatric condition tend to pair up with others who share their diagnosis.

A widely used diagnostic test for autism can reliably distinguish the condition from attention deficit hyperactivity disorder, but not always.

Children who have both attention deficit hyperactivity disorder and autism receive their autism diagnosis an average of four years later than those who have autism alone.

Researchers in Sweden are assembling a large group of identical twin pairs, with only one twin in each pair having autism.

An analysis of blood samples from nearly 17,000 individuals with autism points to new regions of the genome likely to be involved in the disorder.

The ability to recognize emotions varies along a continuum that spans autism, attention deficit hyperactivity disorder and obsessive-compulsive disorder.

Some children shed the symptoms of autism and eventually lose their diagnosis. What sets them apart?

Most men with autism have other psychiatric disorders such as depression, finds a study of 50 men diagnosed with the disorder more than 20 years ago. The findings highlight the range of challenges for adults with autism, many of whom lack the help they need.

Alterations to chromosome 7 lead to changes in the chemical marks that direct gene expression.

DNA sequences called enhancers — which boost the expression of genes from within or outside them — are enriched for genetic variants linked to autism, suggests a new study. The finding may help researchers understand how variants outside genes contribute to autism.