In order to resolve this conflict, a meta-analysis was performed to examine the association between XRCC1 polymorphisms and thyroid cancer risk, by critically reviewing 11 studies on XRCC1 Arg399Gln (a total of 1729 cases and 3774 controls), 7 studies on Arg194Trp (1040 cases and 2487 controls), and 8 studies on Arg280His (1432 cases and 3356 controls). This evidence concerns the gene XRCC1 and thyroid cancer.