Abstract

The aim of this study was to investigate the possible association of three single nucleotide polymorphisms (SNPs), C194T, G399A, and G280A, in the X-ray repair cross-complementing group 1 (XRCC1) gene with the risk of developing colon cancer in Saudi patients. Samples of 65 colon cancer patients, aged 45 to 80 years old, and 65 age-matched controls were genotyped. The results demonstrated that carriers of the variant A-allele of 280 had a higher risk for colon cancer than carriers of the normal (GG) genotype (OR=2.27; 95% CI 0.89-5.83; P=0.08), and carriers of the variant A-allele of 399 were found to have a lower risk for colon cancer than carriers of the normal (GG) genotype (OR=0.73; 95% CI 0.43-1.23; P=0.23). Additionally, the genotype combination showed that the individuals carrying XRCC1 280GA and 399GG genotypes had an elevated risk for colon cancer (OR=3.73; 95% CI 1.14-12.27; P=0.03), whereas subjects carrying the XRCC1 280GA and 399GA genotypes had a decrease risk for colon cancer (OR=0.44; 95% CI 0.04-4.63; P=0.63). These results suggest that the A-allele of 280 might be a risk factor and the A-allele of 399 a protective factor for colon cancer risk.

Key words: XRCC1 gene, SNPs, colon cancer, Saudi.