Genes may predict response to ADHD medication

Testable genetic differences might be used to predict the effectiveness of a medication commonly prescribed to treat attention deficit hyperactivity disorder, a new study suggests.

"This is an exciting finding because ADHD is such a common disorder and it's often difficult to know how patients will respond to ADHD medications," said Dr Mark Stein, principal investigator of the study and director of the Hyperactivity, Attention and Learning Problems Clinic at the University of Illinois at Chicago. "Our hope is to take a lot of the guesswork out of why some people respond to these medications and others do not."

The study found that children with a variant form of a dopamine transporter gene - a variant known to be associated with ADHD - responded poorly to one of the most common stimulant medications, methylphenidate. The transporter gene encodes a protein on the nerve cell membrane that helps to clear the neurotransmitter dopamine from the nerve junction.