Expressions of violent behavior such as aggression are influenced by a complex and dynamic interplay of biological, psychological and social variables. Individual differences in aggressive behavior are at least partly heritable and presumably result from the interaction between genetic and environmental factors [1]. Gene-environment interactions (G×E) refer to genetic differences in susceptibility to particular environmental risk factors. It is well documented that early life environmental risk factors have detrimental effects on the long-term mental health of individuals and increasing evidence suggests that genotype can moderate the capacity of early environmental pathogens to alter risk for mental disorders [2]. In the development of adult antisocial and violent behavior, the environmental factors considered influential include in utero exposure to pathogens and birth complications [3], childhood abuse or neglect [4], [5], and family relationships, home environment, and other social variables [6].
