Neurofibromatosis (NF), is a genetically inherited disorder that is characterized by brown blotches and abnormal growths across the skin and along the nerves. There are seven types of NF, with NF1 (also known as von Recklinghausen disease) being the most common and best-characterized form that has diagnostic skin implications. This disorder affects approximately 1 in 3000 individuals.

Up to 50% of cases of NF1 have been seen in individuals whose parents did not have the disease. This suggests up to half of all individuals with NF1 have a spontaneous mutation in their gene(s). The other half of patients with NF1 have parents that have been affected.