Neurofibromatosis type 1 (NF1, formerly Recklinghausen’s disease) is a genetic tumor predisposition syndrome in which the mutation of a tumor suppressor gene (neurofibromin) leads to the development of mostly benign neurofibromas of the skin and the central and peripheral nervous systems and malformations or tumors of other organ systems. This evidence concerns the gene NF1 and neurofibromatosis type 1.