Xu et al. examined eight BRCA1 SNPs in 303 cases of differentiated thyroid carcinoma in the United States [47]; haplotypes that carried the rs799917 variant allele were significantly associated with a decreased risk of thyroid cancer, and the AG/GG genotypes of rs1799950 were associated with a reduced cancer risk, with an adjusted odds ratio of 0.31. Here, BRCA1 is linked to thyroid cancer.