Candidate Gene Studies of Attention Deficit Hyperactivity Disorder

Attention-deficit/hyperactivity disorder (ADHD) is a common psychiatric condition that affects approximately 5-10% of children worldwide. This disorder is defined by a combination of symptoms of inattention and hyperactivity/impulsivity. Although twin studies demonstrate that ADHD is a highly heritable condition, molecular genetic studies suggest that the genetic architecture of ADHD is complex. Molecular genetic studies support the thesis that dopaminergic, serotonergic, and noradrenergic neurotransmission pathways account for the etiology of this complex disease. This article reviews the latest findings on the molecular genetics of ADHD.