Mutation inDSG1causing autosomal dominant striate palmoplantar keratoderma

Conflicts of interest: none declared. Sir, Striate palmoplantar keratoderma (SPPK; OMIM 148700) is a rare, mainly autosomal dominant, genodermatosis characterized by linear hyperkeratosis of the volar aspects of the fingers, extending onto the palm.1 There is strong evidence that SPPK is caused by defects in desmosomes, the major epithelial intercellular adhesion junctions, which confer strength and rigidity to tissues that experience high mechanical stress. Causative mutations in genes encoding the desmosomal proteins desmoglein 1 (Dsg1) and desmoplakin (DP), and keratin 1 which links to desmosomes, have been reported in 20 cases.2–7 We report a novel mutation in the DSG1 gene in a three‐generation kindred in which four members were affected with SPPK. The proband (II‐1) was a 40‐year‐old Scottish man (Fig. 1a). He presented with painful thickening of the skin on his palms (Fig. 1b) and soles, hyperhidrosis and intermittent associated blistering, since childhood. Clinical examination showed linear hyperkeratosis of the volar aspect of fingers, more extensive focal plantar hyperkeratosis and mild hyperkeratosis of the knees. His father, paternal uncle and 8‐year‐old daughter were similarly affected.