Genetic Tests for Autism Debut Amid Concerns About Validity

A genetic panel intended to predict the risk of developing autism debuted for clinical use in April, while another is in commercial development and a third was published in Molecular Psychiatry in September. But some experts are concerned, saying the tests are based on preliminary scientific evidence.Several tests for autism are already in widespread clinical use, but those detect rare genetic variants that account for only a small percentage of cases.The new tests instead analyze combinations of common markers. Two of the new tests detect single-gene variants, and the third looks at expression patterns of several hundred genes in blood.As the cost of sequencing continues to plummet, experts say families are likely to be offered a dizzying array of similar tests that claim to screen for autism.The average child with autism is diagnosed at age 4 — several years after symptoms emerge and after behavioral interventions are thought to be most effective.For this reason, scientists have been searching for an early and reliable biomarker of the disorder. So far, however, studies of several thousand people with autism or other psychiatric disorders have failed to find any predictive genetic combinations."We need to be more solid on this data before you’re giving a flyer to a family and saying, ‘Spend some money and this might give you some information,’” says Richard Anney, assistant professor of neurodevelopmental molecular genetics at Trinity College Dublin, who was not involved in the new tests.Read more at...SFARI, November 2012.