July 6, 2011
CHICAGO — Environmental factors may play a greater role in autism than previously thought, tipping the scale away from a strict focus on genetics, two studies suggest.
In one, a team at Stanford University compared cases of autism in identical and fraternal twins and found that fraternal twins — who share only half of the same genes — have unusually high rates of autism, suggesting that factors other than genetics may be triggering the disease.
In another, researchers at health insurer Kaiser Permanente found mothers of children with autism were twice as likely to have been prescribed a common antidepressant during the year before their pregnancy than mothers of healthy children.
Both studies were released Monday.