Acantholytic dyskeratotic epidermal naevus and striate palmoplantar keratoderma associated with DSG1 mutation: evidence for segmental type 2 mosaicism

Abstract

Striate palmoplantar keratoderma (SPPK) is a rare autosomal-dominant form of PPK, characterized by linear hyperkeratosis of the volar aspects of the fingers extending onto the palm and focal to diffuse hyperkeratosis of the soles. The type 1 of SPPK (MIM148700) is associated with heterozygous mutations in desmoglein1 (DSG1) (1).Skin manifestations are generally limited to palms and soles (2-4). In contrast, bi-allelic loss of function mutations of DSG1 have been shown to be responsible for the severe dermatitis, multiple allergies and metabolic wasting (SAM syndrome) (5,6).