alters cessation for specific pharmacological treatments (i.e nicotine patch). For example, one study suggested that the association between CHRNA5-A3-B4 variants (rs16969968 [Bin A] and rs680244 [Bin B]) and smoking cessation is primarily observed among smokers treated with placebo, and was not observed among those who received active pharmacological therapy (17). In contrast, another study reported significant associations between CHRNA5-A3-B4 variant (rs1051730 which is in high linkage disequilibrium with rs16969968) and smoking cessation outcomes in smokers who were receiving nicotine replacement therapy with little effect observed in the placebo arm (15). A recent study also observed a treatment by genotype interaction on smoking cessation outcomes (i.e. the genotype effects are in opposite directions for placebo vs. nicotine replacement therapy) (20).
