MAP2K1 and cardiofaciocutaneous syndrome: For instance, mutations in BRAF (B-Raf proto-oncogene, serine/threonine kinase), MAP2K1 (mitogen-activated protein kinase kinase 1, alias MEK1), MAP2K2 (alias MEK2), and KRAS (KRAS proto-oncogene, GTPase) are associated with cardio-facio-cutaneous syndrome, in which ID is present in the majority of patients [30].