Scientists link autism to DNA regions

ST. LOUIS, May 14 (UPI) -- U.S. scientists using a statistical approach have discovered regions of DNA that appear to be linked with autistic spectrum disorders.

The researchers at the Washington University School of Medicine in St. Louis and the University of California-Los Angeles identified two regions of DNA linked with autism. They found the suspicious DNA with a much smaller sample of people than has been used traditionally in searches for autism genes.

Co-principal investigator Dr. John Constantino of Washington University said past research has isolated a few regions of DNA linked to autism, but very few of those studies have been replicated, so no specific autism genes have yet been identified.

"Those older studies used what's called an 'affected sib pair' design that looks for genetic markers in siblings with autism," said Constantino. "That approach has worked well for single-gene disorders, but autism is a complex disease that may involve many genes that each make very small contributions. When that's the case, it's harder to find genetic markers."

Constantino and co-principal investigator Dr. Daniel Geschwind of UCLA detail their study in the April issue of the American Journal of Psychiatry.