Study finds genetic clues to autism

Scientists revealed the most extensive findings to date on the genetics of autism Sunday, pinpointing two new genetic links that may predispose children to the disorder.

Doctors have long known autism runs in families. Now scientists have scanned DNA from 1,168 families with multiple cases, the largest such group ever assembled, and identified gene variants that could one day produce treatments for a disorder that leaves about 1 in 150 U.S. children uncommunicative, cut off emotionally from the world around them.

The five-year study, led by a consortium of researchers from 19 nations, indicated autism had numerous genetic origins rather than a single or a few primary causes.

“This is the most ambitious effort yet to find the locations of genes that may confer vulnerability to autism, revealing clues that will likely influence the direction of autism research for years to come,” said Elias A. Zerhouni, director of the U.S. National Institutes of Health.

The NIH helped sponsor the work done by 120 scientists and 50 institutions in 19 countries, a group known as the Autism Genome Project.

The findings include a deleted gene, called neurexin 1, that enables communication between the nerve cells in the brain that transmit information to the body through chemical and electrical signals. The researchers also found variants in two chromosomes that have never been linked with autism.

The scientists hope that nailing down the genetics of autism will lead to better diagnosis and drugs. They announced they were launching a new phase in the research to map genes responsible for autism.

Geneticist Stephen Scherer of the Hospital for Sick Children in Toronto, who worked on the study, said 90% of autism might have a genetic basis.

“What we have now that we didn’t really have before is a pretty decent understanding of what the genetic architecture is looking like in the autism genome,” he said.