A new germline mutation in KIT associated with diffuse cutaneous mastocytosis in a C hinese family

Summary Diffuse cutaneous mastocytosis ( DCM ) is an extremely rare disease characterized by massive proliferation of mast cells infiltrating the entire skin. We report a Chinese family with indolent DCM , and detection of a new germline KIT mutation located in the fifth immunoglobulin‐like loop of the KIT protein, which probably results in a gain‐of‐function effect and consequent overactivation of mast cells. Our report expands the knowledge of correlations between the genotype of KIT mutations and the phenotype of DCM .