Hereditary palmoplantar keratoderma (PPK) is characterized by hyperkeratosis of the skin of palms and soles. Lind et al. (1994) described an autosomal dominant form of diffuse nonepidermolytic PPK, designated PPK type Bothnia (PPKB), which has a high prevalence of 0.3 to 0.55% in the 2 northernmost provinces of Sweden, situated to the west and the northwest of the Gulf of Bothnia. The Bothnian form is frequently complicated by fungal infections and lacks the histopathologic features distinctive of epidermolytic PPK (EPPK; 144200). For discussion of phenotypic and genetic heterogeneity of palmoplantar keratoderma, see epidermolytic PPK (144200). [from OMIM]