Association of CHRNA5-A3-B4 SNP rs2036527 with smoking cessation therapy response in African American smokers

Associations between CHRNA5-A3-B4 variants and smoking behaviors exist, however the association with smoking abstinence is less understood, particularly among African Americans. In 1295 African Americans enrolled in two clinical trials, we investigated the association between CHRNA5-A3-B4 and smoking abstinence. Rs2056527[A] was associated with lower abstinence with active pharmacotherapy (during-treatment: OR=0.42&P<0.001; end of treatment (EOT): OR=0.55&P=0.004), or with nicotine gum alone (during-treatment: OR=0.31&P<0.001; EOT: OR=0.51&P=0.02), but not significantly with bupropion, although similar directions and magnitudes were observed (during-treatment: OR=0.54&P=0.05; EOT: OR=0.59&P=0.08). Additionally, rs588765[T] was associated with abstinence with gum during treatment (OR=2.31&P<0.01). Rs16969968 occurred at a low frequency and was not consistently associated with abstinence. CHRNA5-A3-B4 variants were not associated with tobacco consumption and adjustments for smoking behaviors did not alter the associations with smoking abstinence. Together, our data suggest that in African Americans CHRNA5-A3-B4 variants are not associated with baseline smoking, but can influence smoking abstinence during active pharmacotherapy.