The clinical relevance of the most frequently mutated genes in follicular cell derived carcinomas, e.g., BRAF, TP53, and NRAS is still not uniform; BRAFV600E occurs in about 29–83% of cases and is the most common molecular aberration in thyroid cancer (24) and is frequently associated with tumor aggressiveness and poor prognosis due to a constitutive activation of the mitogen-activated protein kinase 1 (MAPK) signaling pathway. The gene discussed is MAP2K1; the disease is thyroid cancer.