CYP2A6 and lung cancer: Two genotypes were detected in CYP2A6*9; heterozygote AC and homozygote CC.AC genotype was found in 4 cases in control group; 3 males and 1 female, all cases were non-smokers and 6 cases in lung cancer group; 4 males and 2 females from which 2 males were smokers > 20 pack-year.