Here we used two placebo controlled clinical trials to compare the influence of CHRNA5-A3-B4 variants on smoking cessation outcomes in African Americans treated with placebo and active pharmacological treatments. We hypothesized that there would be a significant association between CHRNA5-A3-B4 gene variants and smoking cessation outcomes in the active pharmacological treatment arms as previously reported by Munafò and colleagues (15). Since rs16969968 occurs at a relatively low allele frequency in African Americans, we focused initially on rs2036527, which has previously been significantly associated with CPD and lung cancer risk in African American (21, 23); we then extended the investigation to rs16969968 (‘Bin A’), rs588765 (‘Bin B’) and rs578776 (‘Bin C’).
