XRCC1 polymorphisms and risk of colorectal cancer: a meta-analysis.

Purpose: Previous studies investigating the association between X-ray repair cross-complementation group 1 (XRCC1) polymorphisms and colorectal cancer (CRC) risk has provided inconsistent results. The aim of our study was to clarify the effects of XRCC1variants on CRC risk.

Materials And Methods: We conducted searches of the published literature in PubMed, Embase, and CBM databases up to July 6, 2009. Meta-analysis was performed by critically reviewing 14 studies with a total of 2,776 CRC cases and 4,402 controls on Arg399Gln polymorphism, four studies with a total of 931 CRC cases and 1,547 controls on Arg280His polymorphism, and nine studies with a total of 1,709 CRC cases and 3,233 controls on Arg194Trp polymorphism, respectively. Statistical analysis was performed with the software programs Review Manager (version 5.0.10) and STATA (version 9.2).

Results: No significant association between Arg399Gln polymorphism and CRC risk was observed in both total population analyses and subgroup analyses based on ethnicity (OR(Co-dominant model) = 1.04, 95% CI 0.74-1.45, P (OR) = 0.82; OR(Dominant model) = 1.02, 95% CI 0.80-1.30, P (OR) = 0.88; OR (Recessive model) = 1.04, 95% CI 0.81-1.34, P (OR) = 0.78). Arg280His polymorphism also had no significant association with CRC risk (OR(Co-dominant model) = 0.85, 95% CI 0.32-2.31, P (OR) = 0.76; OR(Dominant model) = 1.11, 95% CI 0.87-1.40, P (OR) = 0.40; OR(Recessive model) = 0.85, 95% CI 0.32-2.31, P (OR) = 0.75). Besides, there was also no evidence of association between Arg194Trp polymorphism and CRC risk (OR(Co-dominant model) = 1.43, 95% CI 0.83-2.48, P (OR) = 0.20; OR(Dominant model) = 1.14, 95% CI 0.87-1.51, P (OR) = 0.34; OR(Recessive model) = 1.32, 95% CI 0.82-2.13, P (OR) = 0.25).

Conclusions: No association is found between the polymorphisms in XRCC1 (Arg399Gln, Arg280His, and Arg194Trp) and risk of colorectal cancer.