Autism Largely Caused by Genetics, Not Environment

The largest study of its kind, involving more than 2 million people across five countries, finds that autism spectrum disorders are 80% reliant on inherited genes.
That means that environmental causes are responsible for just 20% of the risk.
The findings could open new doors to research into the genetic causes of autism, which the U.S. Centers for Disease Control and Prevention now says affects 1 in every 59 U.S. children.