A positive association between a polymorphism in the <i>HTR2B</i> gene and cocaine-crack in a French Afro-Caribbean population

Cocaine dependence has a strong heritability component. The aim of this study was to investigate the putative association between the serotonin 2B receptor gene (HTR2B), crack use disorders and impulsivity. A French Afro-Caribbean male population of patients with crack use disorders (n = 80) was compared to healthy Afro-Caribbean male controls (n = 60). Comorbid ADHD and impulsivity were assessed. Five single nucleotide polymorphisms (SNPs) in the HTR2B gene were selected: rs643700, rs6736017, rs1549339, rs17586428 and rs3806545. These SNPs were chosen to include most of the linkage disequilibrium blocks in the HTR2B gene. The French translation of the Barratt Impulsivity Scale BIS-11 was used to evaluate impulsivity. Comorbid ADHD was diagnosed using the Wender Utah Rating Scale-25 item for Attention Deficit-Hyperactivity Disorder. We have observed a positive association between the rs6736017 polymorphism and crack use disorders in a French Afro-Caribbean male population. In our population, the risk effect of HTR2B rs6736017 appeared to be specific to individuals with crack use disorders rather than being driven by impulsivity or ADHD alone.