Dermatopathology and molecular genetics

Disadhesion of epidermal keratinocytes: A histologic clue to palmoplantar keratodermas caused by DSG1 mutations

“…[1][2][3] Recent developments in molecular genetics have enabled regrouping of various entities and syndromes leading to more precise histopathologic classifications. 4 Keratosis palmoplantaris striata (KPS) is a rare autosomal-dominant form of PPK characterized by linear hyperkeratotic streaks along the volar surface of the fingers, and focal keratoderma of the soles. Non-sense and frame-shift mutations in DSG1, DSP, and KRT1 genes encoding desmoglein 1, desmoplakin, and keratin 1, respectively, have been shown to be the underlying causes of KPS types I, II, and III, respectively.…”