Studies investigating the basis of FNMTC have identified 4 susceptibility genes, SRGAP1 (SLIT-ROBO Rho GTPase Activating Protein 1), FOXE1 (Forkhead Box E1), SRRM2 (Serine/Arginine Repetitive Matrix 2) and NKX2.1 (NK2 Homeobox 1) [10–12]. This evidence concerns the gene NKX2-1 and familial papillary or follicular thyroid carcinoma.