But which environmental factors remain a mystery
(NEWSER) - Burgeoning cases of autism are strongly linked to the environment, researchers have discovered. A study of twins indicates that while genetics plays a role, the environment is a more significant factor. The study used results among both identical and fraternal twins, and a mathematical formula that determined that genetics accounts for a 38% risk of autism, while environment factors account for 62%, reports the San Francisco Chronicle . "We've known that genetics played a huge role. The surprise was that the environmental factors have been underestimated," said spokeswoman for a patient advocacy group that participated in the California study. More»