10 These studies were conducted in healthy populations and included only whites. Most recently, Le Marchand et al.12 demonstrated that variants in CHRNA3 (rs1051730, and included in this study) and CHRNA5 (rs16969968, which is in near perfect LD with rs1051730 in whites) alter internal dose of a carcinogenic tobacco-specific nitrosamine per cigarette smoked, as measured in urine. Although that study included small numbers of African Americans, results were not presented by race. Taken together, reported findings suggest that more sensitive markers of smoking dose are needed to fully understand the genetics underlying nicotine dependence and lung cancer.
