Assessment of the association between hOGG1 C8069G polymorphism and colorectal cancer

Human oxoguanine glycosylase 1 (hOGG1) is an important part in the base excision repair (BER) pathway of DNA repair. Numerous epidemiological studies were published to assess the association between hOGG1 C8069G polymorphism and risk of colorectal cancer, but they reported contradictory results. A meta-analysis was performed to clarify the effect of hOGG1 C8069G polymorphism on colorectal cancer. The association was assessed by calculating the pooled odds ratio (OR) with 95 % confidence interval (95 %CI). Twenty-one studies with a total of 14,492 participants were finally included into the meta-analysis. Overall, there was an obvious association between hOGG1 C8069G polymorphism and increased risk of colorectal cancer under all four genetic models (G vs. C: OR = 1.17, 95 %CI 1.05-1.30, P = 0.003; GG vs. CC: OR = 1.39, 95 %CI 1.11-1.74, P = 0.004; GG/CG vs. CC: OR = 1.20, 95 %CI 1.04-1.37, P = 0.010; GG vs. CC/CG: OR = 1.23, 95 %CI 1.03-1.46, P = 0.020). Subgroup analysis based on ethnicity showed that there was an obvious association between hOGG1 C8069G polymorphism and increased risk of colorectal cancer in the Caucasian population but not in the Asian population. The findings from the meta-analysis suggest that there is an obvious association between hOGG1 C8069G polymorphism and increased risk of colorectal cancer, especially in the Caucasian population.