In conclusion, in this study, we demonstrated an association of allelic variation in PER2 gene with alcohol use in a sample of young adults from the community, replicating the findings of Spanagel et al. [11] in a patient sample. Carriers of the protective variant drank less frequently in total, and displayed fewer alcohol-related problems following exposure to stressful life events. Future research will have to disentangle the actual pathways by which stressful life events affect alcohol use in order to contribute to a better understanding of the underlying mechanisms. However, in light of the likely burden of multiple tests, the nature of the measures used and the nominal evidence of interaction, the GxE interaction reported here needs replication in independent samples, before firm conclusions can be drawn.
