The serotonin 5-HT1D receptor gene and attention-deficit hyperactivity disorder in Chinese Han subjects

Attention-deficit/hyperactivity disorder (ADHD) is a heritable disease. Serotonin is one of the neurotransmitters involved in the etiology of ADHD. Serotonin-1D receptors are autoreceptors which can regulate the release of serotonin in brain, so the HTR1D gene may be predisposing. The current study genotyped two variants of HTR1D gene in 272 ADHD trios of Chinese ethnicity, that is 1350T > C in the coding region and 1236A > G in 3′-UTR by the use of transmission disequilibrium test (TDT). The A allele of the 1236A > G polymorphism exhibited both a trend toward preferential transmission to ADHD probands (χ² = 3.815, P = 0.051) and a significant preferential transmission to probands of ADHDC (χ² = 4,198, P = 0.040). Additional polymorphisms in this gene need to be studied further.