Among the bupropion-treated subjects and in all three treatment groups combined, continuous abstinence at weeks 9–12 was strongly associated with several SNPs in CYP2B6 as well as two SNPs in CHRND, which encodes the nAChR delta subunit. Interestingly, one of the CYP2B6 SNPs (rs8109525; Figure 1b) is contained within a LD bin that includes rs7260329, a SNP recently identified to be significantly associated with the number of cigarettes smoked per day (Thorgeirsson et al, 2010). rs7260329 itself is nominally associated with continuous abstinence in the bupropion and combined populations, although to a lesser degree (p<0.008, p<0.02, respectively; q values >0.2). No SNP tested was significantly associated with abstinence on placebo treatment.
