DAT1 polymorphism associated with poor decision-making in males with antisocial personality disorder and high psychopathic traits.

Studies suggest that abnormalities of the dopaminergic system underlie decision-making deficits, a hallmark of antisocial personality disorder (ASPD) and psychopathy. The dopamine transporter gene (DAT1) is of particular interest due to a polymorphism that controls dopamine transporter (DAT) activity. However, the association between DAT1 genotypes and decision-making in ASPD has never been studied. The current study investigated the effect of DAT1 genotype on decision-making, as measured by the Iowa Gambling Task (IGT), in ASPD and healthy controls. A total of 17 participants with ASPD and 16 healthy control participants without ASPD were sampled. The Hare Psychopathy Checklist-Revised and the IGT were administered to all participants. All participants provided blood samples for genotyping. Data revealed a novel interaction effect between DAT1 genotype and diagnosis, whereby ASPD participants with low DAT activity genotypes performed significantly worse on the IGT and selected from disadvantageous decks more often, whereas the low DAT activity genotype in the healthy control group was associated with better performance on the IGT, and they selected from disadvantageous decks less often. We demonstrate, for the first time, that low DAT activity genotypes in ASPD with high psychopathic traits contribute to poor decision-making.