PER1 and alcohol drinking: On the other hand, stress-related (i.e., cortisol-induced) transcriptional activation of human PER1 was reduced in a type of human blood cells (i.e., B-lymphoblastoid cells) that carried an altered form of the PER1 gene (i.e., the rs3027172 genotype), which has been associated with an increased risk of alcoholism (Dong et al. 2011).