Genetic Risk of DNA Repair Gene Polymorphisms (XRCC1 and XRCC3) for High Risk Human Papillomavirus Negative Cervical Cancer in Northeast Thailand

To identify risk factors other than high risk human papillomavirus infection for the development of cervical cancer, functional polymorphisms of DNA repair genes, XRCC1 Arg399Gln and Arg194Trp and XRCC3 Thr241Met, were studied among Northeastern Thai women. Cases (n=111) were defined as squamous cell cervical cancer and controls (n=118) were recruited from healthy women without cervical abnormalities. The XRCC1 194Trp/Trp genotype significantly increased the risk for cervical cancer (OR=5.52; 95%CI=1.14-26.64; p=0.03). Among the HPV infection negative group, significantly higher risks for cervical cancer were visualized for XRCC1 399Arg/Gln (adjusted OR=3.69; 95%CI=1.04-13.06; p=0.04) and XRCC1 194Arg/Trp (adjusted OR=4.13; 95%CI=1.13-15.12; p=0.03). This study indicates that variant types of DNA repair genes play partial roles in modifying individual susceptibility to cervical cancer. Since cervical cancer is a multi-factorial disease, the contribution of DNA repair enzymes to the development of cervical cancer, if it exists may be concealed by HPV infection.