would influence the siblings being raised in the same family similarly, and manifest itself as a shared environmental effect on alcohol related behavior. This is providing that there is variation among religious households in their attitudes towards drinking. For example, it has been demonstrated that Catholics are more at risk for alcohol related phenotypes than other religious affiliations (Heath et al. 1997), and this might be reflected in the etiology of alcohol phenotypes. This finding was replicated for adult males in the current study.
