With a birth incidence of approximately 1:3000, Neurofibromatosis type 1 is caused by dominantly inherited mutations in NF1 (MIM 613113) [8], a complex gene [9] encoding for neurofibromin, a GTPase-activating protein that negatively regulates the Ras/MAPK signaling pathway [10]. This evidence concerns the gene NF1 and neurofibromatosis type 1.