SASH1 and Palmoplantar keratoderma: To date, 17 heterogeneous missense mutations in SASH1 have been confirmed to be associated with pigmentation disorders, among which eight mutations result in DUH [5, 11, 12] and nine are responsible for multiple lentiginous phenotypes [13–16]; furthermore, the missense mutation c.1849G>A was reported to result in a loss of pigmentation with palmoplantar keratoderma and skin carcinoma [17].