NF1 and neurofibromatosis: Additional variants of neurofibromatosis such as variant neurofibromatosis (NF4), segmental neurofibromatosis (NF5), and multiple café au lait syndrome (NF6) have been described; however, most patients with these diagnoses exhibit alterations in the NF1 gene on chromosome 17, suggesting that they may represent variant presentations of NF1, possibly as a consequence of genetic mosaicism, rather than distinct syndromes [14].