Aim: To examine the genetic and environmental influences of parental alcoholism on offspring disinhibited behavior.
Design: We compared the effect of parental alcoholism history on offspring in adoptive and non-adoptive families. In families with a history of parental alcohol dependence, we examined the effect of exposure to parental alcoholism symptoms during the life-time of the adolescent. Setting Assessments occurred at the University of Minnesota from 1998 to 2004.
Participants: Adolescents adopted in infancy were ascertained systematically from records of three private Minnesota adoption agencies; non-adopted adolescents were ascertained from Minnesota birth records. Adolescents and their rearing parents participated in in-person assessments.
Measurements: For adolescents, measures included self- reports of delinquency, deviant peers, substance use, antisocial attitudes and personality. For parents, we conducted DSM-IV clinical assessments of alcohol abuse and dependence.
Findings: A history of parental alcohol dependence was associated with higher levels of disinhibition only when adolescents were related biologically to their rearing parents. Within families with a history of parental alcoholism, exposure to parental alcohol misuse during the life-time of the adolescent was associated with increased odds of using alcohol in adopted adolescents only.
Conclusions: These findings suggest that the association between a history of parental alcohol dependence and adolescent offspring behavioral disinhibition is attributable largely to genetic rather than environmental transmission. We also obtained some evidence for parental alcohol misuse as a shared environmental risk factor in adoptive families.