Loss-of-function variants in the NF1 tumor suppressor gene (MIM *613113) cause neurofibromatosis type 1 (NF1, MIM #162200), which has one of the highest spontaneous mutation rates across all monogenic human disorders, described as up to 1 × 10–4 (Huson et al. 1989). This evidence concerns the gene NF1 and neurofibromatosis type 1.