Cluster 2 mutations involve germline mutations of the rearranged-during-transfection (RET) oncogene associated with MEN 2A/2B disease, neurofibromin (NF1), transmembrane protein 127 (TMEM127), Myc-associated factor (MAX) and somatic mutations of HRAS and fibroblast growth factor receptor 1 (FGFR1) genes [12]. This evidence concerns the gene RET and multiple endocrine neoplasia type 2A.