Adolescent patients (ages 13-18) were recruited from a university substance abuse treatment program (n=371). Close age siblings were also invited to participate, as were parents of patients. Two hundred and forty five full siblings of patients gave written informed consent, completed diagnostic instruments for CD/AD and provided a DNA sample. Three hundred and fifty five parents of patients (113 fathers and 242 mothers) provided a DNA sample which was genotyped for rs279871.
