BackgroundThe Taql-A polymorphism of the ANKK1 gene, adjacent to the DRD2 gene, has been associated with alcoholism and other psychiatric conditions, although other DRD2 gene variants, such as the C957T polymorphism, could be related to these phenotypic traits.AimsTo investigate the contribution of the Taql-A and the C957T polymorphisms to the presence of psychopathic traits in patients with alcoholism.MethodWe performed association and interaction analyses of the polymorphisms in 150 controls and 176 male alcohol-dependent patients assessed for the presence of dissocial personal disorder, using the Psychopathy Checklist-Revised (PCL-R).ResultsThere was a significant association of the Taql-A and C957T polymorphisms when both genotypes were present, with PCL-R scores of F_1–171=0.13 (P=0.01) and a frequency of dissocial personal disorder OR=10.52, P<0.001.ConclusionsThe Taql-A of the ANKK1 gene and the C957T of the DRD2 gene are epistatically associated with psychopathic traits in alcohol-dependent patients.