A twin study of self-reported psychopathic personality traits

Previous twin studies attempting to assess the origins of psychopathic personality traits have mainly focused on an overt behavioral conceptualization of the syndrome as defined by a history of chronic antisocial behaviors. This investigation instead focused on a personality-based approach which emphasizes maladaptive personality traits as central to the syndrome. Psychopathic traits were indexed by the Psychopathic Personality Inventory (PPI), a self-report measure designed to assess the personality domain of the disorder. Biometric parameters obtained from the responses of 353 male twins from the Minnesota Twin Registry revealed significant genetic influences, largely non-additive in nature. Although preliminary due to the modest sample size, the findings encourage a larger scale investigation with greater statistical power to evaluate competing models of genetic influence.