To determine whether these results could be replicated with an earlier study, data from a previously published study33 were reanalyzed. This previous study allowed us to examine the interaction between a medication that targets the dopamine system (olanzapine) and rs2023239. The analyses involved a 2 (medication: olanzapine vs cyproheptadine hydrochloride) × 2 (genotype: TT vs CT and CC) × 3 (drink: 1 vs 2 vs 3) repeated-measures ANOVA. The analyses revealed a genotype × drink interaction (F2,112 = 5.19, P = .01) such that individuals with the CT genotype reported greater reward from the alcoholic beverages. There were no significant genotype × medication interactions on this measure (P > .05). In lieu of positive affect, we examined self-reported high. The analyses revealed a significant medication × genotype × drink interaction on self-reported high (F2,112 = 3.39, P < .05). Individuals with the CT (or CC) genotype (n = 9) who received the active control medication (cyproheptadine) reported the greatest high after the third drink (Figure 4C). There were no significant differences between individuals with the CT genotype and those with the TT genotype for the olanzapine condition (Figure 4D).
