Scientists say they’ve identified two variants of a single gene that might raise a child’s risk of autism by twofold or more.
The variants are fairly common and can’t bring on the disease by themselves, the researchers said. Scientists believe several genes, perhaps five to 10, have to work together to produce autism.
Previous studies have identified variants in other genes that might contribute to the disease but none has been proven to do so. Finding autism-related genes might help scientists develop treatments for the perplexing disorder.
More studies needed
The new work provides strong evidence that the gene influences susceptibility to autism, but more studies will be needed to confirm the link, said lead study author Joseph Buxbaum of the Mount Sinai School of Medicine in New York.
“It looks like they might have something there ... but it’s a bit too soon to say definitively,” said Susan Santangelo, a Harvard expert not involved in the study.
The study appears in the April issue of the American Journal of Psychiatry.
Autism, which normally appears by age 3 and usually in boys, interferes with a child’s ability to communicate and interact with others. Affected children might not respond to their names or even look at other people.
The new study looked at 411 families, analyzing DNA from more than 2,000 people. Of those, 720 had autism.
The study found that the two gene variants had been inherited by family members with autism more often than one would expect by chance. That implicates the variants in the disease.
The gene is involved in providing energy to brain cells, so variant versions might hamper the operation of those cells, the researchers said.