Contribution of 5‐HT2A receptor gene ‐1438A>G polymorphism to outcome of attention‐deficit/hyperactivity disorder in adolescents

Abstract

Attention-deficit/hyperactivity disorder (ADHD) typically emerges before 7 years of age and may persist into adolescence or adulthood. The adolescent outcome can be classified into four types, including non-remission, syndromatic remission, symptomatic remission, and functional remission. Genetic factors are believed to contribute to symptom stability and change across development, so adolescent outcome may be a sub-phenotype for molecular genetic studies of ADHD. Serotonin system genes are prime candidates for this sub-phenotype, since the development of this neurotransmitter system parallels the course of ADHD. The current study examined the association between adolescent outcome in ADHD and serotonin system genes, including the -1438A>G polymorphism of the serotonin 2A receptor gene (HTR2A) and the -759C>T polymorphism of the serotonin 2C receptor gene (HTR2C). The -1438A>G polymorphism was found to be related to remission in ADHD, especially functional remission (P = 0.029). Due to potential phenotypic and etiologic heterogeneity in ADHD, the results of this study must be replicated in additional samples before they can be generalized to other populations.