The aims of the current study were to identify whether religiosity is a protective factor for problem alcohol use in adolescents and young adults, and to examine the extent to which religiosity moderates the magnitude of the genetic influence of problem alcohol use. Consistent with previous findings (e.g. Koopmans et al. 1999) our results suggested that religiosity did significantly protect against the development of problem use in both adolescence and early adulthood. Moreover, we also demonstrated that, consistent with previous work, both the phenotypic variance and genetic variance was attenuated in higher levels of religiosity. However, although the variance was attenuated in both adolescents and young adults, the genetic variance was attenuated only in the adolescents. As discussed below, these findings provide general support for the social control hypothesis.
