Abstract
• The present study follows up adoptees separated at birth from the biologic parents to assess the importance of genetic and environmental factors in adolescent antisocial behavior. The dependent variable is an antisocial symptom count that tallies antisocial but not necessarily criminal behaviors in adolescence. The independent variables are of two types, genetic and environmental. Genetic variables refer to psychiatric diagnoses of the biologic family. Environmental variables are those identified by previous research as associated with adolescent antisocial behavior. Our results indicate that boys are more vulnerable than girls to the adverse effects of a psychiatrically ill adoptive family member or divorce in the adoptive parents. There is not a significant sex difference in genetic predictors. In the total sample, the genetic variables that predict antisocial behavior are having an antisocial or alcoholic biologic relative. This finding is in agreement with other heritability studies of antisocial behavior.