New Tests Show Progress in Identifying Genetic Roots of Autism

One of the most agonizing questions that parents of children with autism ask is—why? Now, a growing number of genetic tests are providing some answers.
Scientists say that roughly 20 percent of autism cases can be linked to known genetic abnormalities, and many more may be discovered.
Pinpointing a genetic explanation can help predict whether siblings are likely to have the disorder—and even point to new, targeted treatments. Last week, for example, researchers reported that an experimental drug, arbaclofen, reduced social withdrawal and challenging behaviors in children and adults with Fragile X syndrome, the single most common genetic cause of autism.