MSH: Autosomal dominant, congenital disorder characterized by localized hypomelanosis of the skin and hair. The most familiar feature is a white forelock presenting in 80 to 90 percent of the patients. The underlying defect is possibly related to the differentiation and migration of melanoblasts, as well as to defective development of the neural crest (neurocristopathy). Piebaldism may be closely related to WAARDENBURG SYNDROME.,NCI: A rare, autosomal dominant disorder caused usually by mutations in the KIT gene. It is characterized by abnormalities in the development of melanocytes. It presents with multiple symmetrical hypopigmented or depigmented patches of skin and a midline patch of white hair.