The genetic and environmental covariation among psychopathic personality traits, and reactive and proactive aggression in childhood

Abstract

The present study investigated the genetic and environmental covariance between psychopathic personality traits with reactive and proactive aggression in 9- to 10-year-old twins (N = 1,219). Psychopathic personality traits were assessed with the Child Psychopathy Scale (D. R. Lynam, 1997), while aggressive behaviors were assessed using the Reactive Proactive Questionnaire (A. Raine et al., 2006). Significant common genetic influences were found to be shared by psychopathic personality traits and aggressive behaviors using both caregiver (mainly mother) and child self-reports. Significant genetic and nonshared environmental influences specific to psychopathic personality traits and reactive and proactive aggression were also found, suggesting etiological independence among these phenotypes. Additionally, the genetic relation between psychopathic personality traits and aggression was significantly stronger for proactive than reactive aggression when using child self-reports.

Figure 1

Standardized squared estimates from the best fitting one-factor independent pathway model are displayed. Note. For simplicity, only one twin in a pair is shown. In the model, genetic and nonshared environmental effects are represented in two ways: general (common among subscales) and specific (unique to each subscale) effects. Latent variables are depicted in circles, A is common additive genetic factor and E is common nonshared environmental factor; A_s (additive genetic) and E_s (nonshared environmental effects) are residual variances specific to each measure. Measured variables are depicted in rectangles (manipulative & deceitful, callous & disinhibited, reactive and proactive aggression). One-factor independent pathway model of psychopathic personality traits and aggression in both caregiver reports and child’s self-reports (child self-report parameter estimates are presented in parentheses). *p < .05.