It is inherited in an autosomal dominant manner. The incidence of NS is estimated to be between 1 in 1,000 to 1 in 2,500 children. [2] NS is caused by mutations in the RAS/mitogen-activated protein kinase (MAPK) pathway which is essential for cell cycle differentiation, growth and senescence. A number of mutations have been identified with the four most common being PTPN11 (50% of cases), KRAS,...
