A hOGG1 gene polymorphism and genetic susceptibility to colorectal cancer and hepatocellular carcinoma

Objective To investigate the possible association between the codon 326 polymorphism(Ser326Cys) of the hOGG1 gene and susceptibility to colorectal cancer(CRC) and hepatocellular carcinoma(HCC) in Chinese population.Methods The hOGG1 Ser326Cys genotype was determined by TaqMan assay in 345 CRC cases and 670 controls,and in 175 HCC cases and 119 controls.Results Generally,there is no correlation between HCC or CRC risk and the Ser326Cys genotypes,and no correlation between CRC risk and the Ser326Cys genotypes among nonsmoking subjects,either.However,in smoking subjects,the 326Cys allele was associated significantly with the presence of CRC(P=0.006) and had a higher risk(OR=1.58,95%CI=1.14～2.19) of CRC as compared to the 326Ser allele.There is a 2.40-fold(95%CI=1.20～4.78,P=0.013) increased CRC risk in the Cys/Cys genotype than that in Ser/Ser genotype,and a 2.02-fold(95% CI=1.21～3.37,P=0.008) increased risk than that in 326Ser-allele carriers(Ser/Ser or Ser/Cys genotype).Conclusion The hOGG1 Ser326Cys polymorphism may be not associated with HCC risk,but the Cys/Cys genotype may contribute to the etiology of CRC among smokers in the Chinese population.