The Study of Esophageal Cancer Risk Associated with Polymorphisms of DNA Damage Repair Genes XRCC4 and RAD51

Objective Investigate the association between genetic polymorphism of DSBs repair gene XRCC4, RAD51 and susceptibility to esophageal cancer (EC). Methods A hospital based case-control study with 123 EC cases and 61 controls in a Chinese population was conducted. PCR-RFLP was applied to investigate the genotype of XRCC4 promoter G-1394T (rs6869366) and RAD51-G135C and then statistical analysis was conducted by calculating the adjusted odds ratios (OR) and 95% confidence intervals (95%CI). Results A significant difference of XRCC4-1394 polymorphism was observed between EC cases and controls (P<0.05). Carriers of the XRCC4 rs6869366 G allele (GC+GG) were at a higher risk of developing EC with the TT genotype as reference (OR=3.022, 95%CI=1.487-6.142, P=0.002). When GG served as the reference group of RAD51-G135C allele, variant genotype (GC and CC) had a significant increased risk of lung cancer (OR=3.643,95%CI=1.501-8.842,P<0.05). Conclusion Our findings indicated that genetic variants in DNA repair pathways may be involved in esophageal tumorigenesis. XRCC4 G-1394T and RAD51-G135C conferred risk for the process of developing EC.