Interactions between genotype and retrospective ADHD symptoms predict lifetime smoking risk in a sample of young adults.

Attention-deficit/hyperactivity disorder (ADHD) symptoms are associated with an increased risk of smoking, and genetic studies have identified similar candidate genes associated with both ADHD and smoking phenotypes. This paper addresses the question of whether ADHD symptoms interact with candidate gene variation to predict smoking risk. Participants were a subsample of individuals from the National Longitudinal Study of Adolescent Health (Add Health), a nationally representative sample of adolescents followed from 1995 to 2002.