Note: Well, at least it's not blaming Mom.

A scientific team led by University of California San Diego School of Medicine researchers says it has identified the cause that may explain why some people develop autism—rare inherited variants in regions of paternal noncoding DNA. Previous studies have demonstrated that de novo mutations contribute to approximately one-third of cases of the disorder. 

The current findings (“Paternally Inherited Cis-Regulatory Structural Variants Are Associated with Autism”) are published online in Science.

The newly discovered risk factors differ from known genetic causes of autism in two important ways. First, these variants do not alter the genes directly but instead disrupt the neighboring cis-regulatory elements, or CREs. Second, these variants do not occur as new mutations in children with autism, but instead are inherited from their parents.

"For ten years we've known that the genetic causes of autism consist partly of de novo mutations in the protein sequences of genes" said Jonathan Sebat, Ph.D., a professor of psychiatry, cellular and molecular medicine, and pediatrics at UC San Diego School of Medicine and chief of the Beyster Center for Genomics of Psychiatric Genomics. "However, gene sequences represent only 2% of the genome."  Read more here.