The circadian rhythm gene period 1 (PER1) is activated by stress hormones and, as was shown in mice, influences stress-related alcohol consumption [68•] and was associated with AD in a large sample of adults [68•]. In a group of 273 individuals aged 18 years, there were G×E effects of adversity and a PER1 promoter single nucleotide polymorphism (SNP) rs3027172 shown to be functional [68•] on drinking behavior such that carriers of the minor C allele who were also exposed to high family adversity had an increased frequency of heavy drinking [68•].
