Taken together, the findings from comprehensive genotyping of 13 SNPs in our large MTC cohort, we showed for the first time, a significant protective risk association of CDKN1A SNP (rs1801270) with MTC and through meta‐analysis of expanded cohort, we also showed a risk association of four RET SNPs with MTC. This evidence concerns the gene CDKN1A and medullary thyroid gland carcinoma.