XRCC1 and nasopharyngeal carcinoma: For the XRCC1 Arg399Gln polymorphism, the risk for developing NPC did not differ between individuals with the Arg/Arg genotype and those with the Arg/Gln genotype (OR = 0.82; 95% CI, 0.62–1.08) or the Gln/Gln genotype (OR = 1.20; 95% CI, 0.69–2.06)(Table 2).