[The RET gene in multiple endocrine neoplasia type 2 (MEN 2)].

Multiple endocrine neoplasia types 2A and 2B(MEN 2A and MEN 2B), and familial medullary thyroid carcinoma(FMTC) are autosomal, dominantly inherited syndromes involving endocrine tumors. MEN 2A is characterized by medullary thyroid carcinoma(MTC), pheochromocytoma(pheo), and parathyroid hyperplasia; MEN 2B is characterized by MTC, pheo, mucosal ganglioneuroma, and marfanoid habitus. Affected individuals in FMTC families develop MTC without any other abnormalities. MEN 2A and MEN 2B and FMTC are caused by germline mutations in the RET proto-oncogene. To investigate the spectrum of RET mutations among Japanese patients, we analyzed the RET gene 118 patients with MEN 2 or FMTC.