RET and medullary thyroid gland carcinoma: Any RET sequence change detected in individuals with a family history of MEN2 symptoms or where MEN2 is suspected (patient with apparent sporadic MTC or Pheochromocytoma) can be compared to the available RET MEN2 database, and also to the benign RET sequence variation present in the large cohort of unaffected individuals that was generated in this paper.