"These findings establish that genetic factors play a strong role in autism spectrum disorder," says Acting NIH Director Raynard Kington, M.D., Ph.D. "Detailed analysis of the genes and how they affect brain development is likely to yield better strategies for diagnosing and treating children with autism."

Autism spectrum disorders (ASD) comprise a group of disorders with core symptoms that include social interaction problems, poor verbal and nonverbal communication and repetitive behaviors. These disorders range from severe (autism) to mild (Asperger’s syndrome), and in total affect some 1 in 150 American children, about three-quarters of whom are boys. Researchers theorize that the social parts of the brain are underdeveloped in ASD.