Signs & Symptoms

Even undiagnosed siblings of children with autism tend to struggle with anxiety, depression and social difficulties.

Fragile X syndrome is a leading genetic cause of autism. People who have either condition often share certain traits, such as difficulties in social situations.

Traits linked to autism and attention deficit hyperactivity disorder tend to co-occur even in adulthood.

People who have a mutation linked to autism plus a second genetic glitch tend to have more severe symptoms than those with the mutation alone.

Toddlers with autism show less fear when confronted with something scary than do typical children or those with developmental delay.

Many drugs for fragile X syndrome have failed in large clinical trials, but candidates that target new aspects of the condition may fare better.

A new behavioral test in zebrafish may help researchers zero in on the biology of social interactions.

Depression is more than three times as common among adults with autism as it is in the general population.