rs588765 and rs1051730 are significantly associated with abstinence (Fig. 1 and See Table, Supplemental Digital Content 7: Effects of chr15q25.1 nAChR SNPs on abstinence, 26 arms). The minor allele of rs588765 is significantly associated with reduced abstinence in the PLA PG at 6MO [0.414 (0.171–0.999) 0.049], and with increased abstinence in the NRT PG at 6MO [2.074 (1.111–3.871) 0.022]. The minor allele of rs1051730 is significantly associated with reduced abstinence in the PLA PG at EOT [0.422 (0.191–0.934) 0.033] and at 6MO [0.312 (0.122–0.802) 0.016], and with increased abstinence in the NRT PG at 6MO [2.540 (1.293–4.987) 0.007]. The effect of rs1051730 on abstinence differs significantly between PGs at 6MO (F6, 28652=2.48, P=0.021). The degrees of freedom of the F statistic reflect imputation of multiple datasets. The significant test of homogeneity is most likely due to the significant and opposite effects of rs1051730 on abstinence in individuals randomized to PLA versus NRT. In sensitivity analyses not adjusting for nicotine dependence measures (See Table, Supplemental Digital Content 8: Effects of chr15q25.1 nAChR SNPs on abstinence, excluding dependence measures, 26 arms), rs1051730 associations with abstinence remain statistically significant with modestly reduced effect sizes.
