Attention-Deficit/Hyperactivity Disorder
Population Genetics
Early family studies of ADHD noted alcoholism and sociopathy in male relatives of children with ADHD and hysteria in female relatives. This same constellation was not manifest in the adoptive parents of adopted children with ADHD.
Recent family studies suggest that ASPD aggregates in the relatives of children with ADHD, but only when the probands have had conduct disorder or oppositional defiant disorder. One study found increased rates of affective illness in relatives of the ADHD probands as well. ADHD itself was also more common in relatives, and ADHD and antisocial behavior tended to occur together.
A report on the association between minor physical anomalies and ADHD found a relationship consistent with a genetic latent trait model (ie, an underlying autosomal dominant gene producing ADHD, physical anomalies, or both). Other findings include a report of mutations in the gene for the thyroid hormone receptor in one group of subjects with ADHD and a family-based association study implicating a gene for the dopamine transporter.
