The primary goal of the current study was to investigate whether the magnitude of the variance components for dependence vulnerability varied as a function of perceived peer delinquency. In terms of the models proposed in the introduction it appears that social distinction is important in adolescents with low PPD scores, as the genetic factors are more salient when perceptions of peers’ delinquency is very low. Conversely, social expression appears to play a role in those with extremely high PPD scores, as the genetic variance is smaller at normative levels of PPD, and increases as adolescents perceive their peers to be more delinquent. In both instances, little change in the genetic variance over the normal range would be expected, and this is evident from the current results. Therefore, a combination of the social distinction and social expression models appears to explain the pattern of results seen here. The mechanisms behind this are unknown but can be speculated about. For instance, in those adolescents who have non-delinquent peers, we would anticipate that the adolescents must have some other predisposition, i.e. a genetic
