Another research of 114 NPC patients proved that the XRCC1 rs25487 GA genotype was significantly associated with the development of grade 3 dermatitis (OR=2.65, 95%CI=1.04-6.73, P=0.037) and was also associated with higher incidence of grade 3 mucositis with a borderline statistical significance (OR=2.11, 95%CI=0.951-4.66, P=0.065) [30]. This evidence concerns the gene XRCC1 and mucositis.