A new study finds children who grow up with an older sibling who has autism have a one in five chance of developing the disorder. The risk is much higher than was previously thought.
Previous research had estimated the risk of autism recurrence within a family to be between three and 10 percent.
The new study was based on observations of more than 650 high-risk infants at 12 sites worldwide, including San Diego.
UCSD professor of psychology Karen Dobkins was involved with the research. She pointed out the cause of autism remains unknown.
"The current study cannot distinguish between the genetics of autism versus environmental factors that might run in families with autism," Dobkins said. "And of course further studies will be needed."
Dobkins said parents who have an older child with autism should be vigilant with their other kids. She says early intervention is crucial with children who have the disorder.
Autism is a complex developmental disorder that affects a person's ability to communicate and relate with others. It usually emerges before a child is three years old.
