Also, 9% of the cases are associated with Von Hippel-Lindau syndrome - VHL (VHL gene), 5% corresponds to multiple endocrine neoplasia 2 syndrome—MEN2 (RET proto-oncogene), and 2% are associated with neurofibromatosis type 1 syndrome—NF1 (NF1 gene). The gene discussed is NF1; the disease is von Hippel-Lindau disease.