Contribution of serotonin transporter polymorphism (5-HTTLPR) to automatic racial bias

• Study examined influence of 5-HTTLPR genotype on implicit/explicit racial bias.
• S-allele carriers exhibited greater implicit racial bias than those with L/L genotype.
• No differences in explicit racial bias observed based on genotype.
• 5-HTTLPR may selectively contribute to implicit, but not explicit racial bias.

Prior research has suggested that basic individual differences in reactivity to threatening or aversive stimuli are predictors of individual differences in racial bias. Despite the role of genes in modulating such individual differences in affective and motivational responses, whether such genes contribute to individual differences in racial bias remain unknown. Here we examined the influence of the serotonin transporter polymorphism (5-HTTLPR) on implicit and self-reported racial bias among a sample of European-Americans. We observed that the short-allele variant of 5-HTTLPR predicted greater levels of implicit racial biases, but not explicit self-reported racial biases. These findings demonstrate that a genetic variant involved in affective response and regulation may contribute to individual differences in the activation of automatic race-related evaluations, although this influence of genes on racial bias may not be readily expressed through deliberative self-report.