The Relationship of XPA and XPC Gene Polymorphisms with the Risk of Colorectal Cancer in Iran

Background: The objective of this study was to investigate the effect of several XPA and XPC polymorphisms on the risk of colorectal cancer (CRC) in northeastern Iran. Method: 180 CRC patients and 160 healthy subjects participated in this case-control study. We determined the genotypes by RFLP-PCR and PIRA-PCR, and analyzed the results using logistic regression and χ2-test. Results: Our findings showed that only BMI could affect the risk of cancer among the studied demographic factors. Three of the four polymorphisms studied, namely XPA A23G, XPC rs2228000 C > T and XPC rs2228001 A > C, did not correlate with CRC (P-values > 0.05); however, the polymorphism of XPC poly AT (PAT) increased the risk of CRC (P= 0.024). The XPC rs2228000 C> T polymorphism increased the CRC risk only in patients aged 50 or more. The risk of CRC in heterozygote individuals (XPC PAT D/I) was higher than that of homozygous individuals (XPC PAT D/D); also, at least one PAT I variant allele increased the likelihood of CRC (for PAT D/I o‎r =2.168; 95% CI = 1.809-4.319: and for PAT D/I and PAT I/I o‎r = 1.810; 95% CI = 1.165-2.813). The XPC haplotypes were similar between the cases and controls, and P-values were >0.05. Conclusion: In the whole population, XPC PAT polymorphism, overweightness, and XPC rs2228000 C>T polymorphism in elderly people are related to CRC. Therefore, they can probably be considered as markers of CRC in Iran.