Genes linked to psychopathy

Six genes have be shown to influence the risk of developing psychopathy: ANKK1, DRD2, DRD4, MAOA, COMT,and 5-HTTLPR. Individual expression of psychopathy related phenotypes depend on which combination of alleles are inherited in addition to environmental factors. In order to be at an elevated risk of psychopathy, an individual must inherit at least four psychopathy related alleles located at, at least, three different loci.

DRD2
In addition to the DRD2 957C/C genotype, the DRD2 Taq1 B allele and polymorphisms in the promoter region of the DRD4 gene have also have been linked to psychopathy. This suggests that the dissocial and impulsive basal endophenotypes can be subdivided into at least seven subtypes: 1a, 1b, 1c, 2, 3a, 3b, and 3c.