Given the role of clock genes and stress in heavy alcohol use, the aim of the present study was twofold: 1) to extend previous findings suggesting an association of PER2 rs56013859 genotype with drinking patterns in an epidemiological cohort study of young adults from a high-risk sample, and 2) to examine a role for this genotype in moderating the effect of exposure to severe stressful life events on hazardous drinking. To consider a possible impact of drinking to cope with stress, only experienced alcohol consumers (i.e. with current regular use) were included in the latter analysis.
