Two different clinical and genetic forms of hereditary palmoplantar keratoderma in the northernmost county of Sweden.

A follow-up study of clinical and genetic observations, made on patients with hereditary palmoplantar keratoderma living in the northernmost county of Sweden (Norrbotten) in 1967, was performed. Two clinical types could be distinguished, a common form with an autosomal dominant mode of inheritance, corresponding to the description of the Unna Thost variety and a severe form with evidently an autosomal recessive inheritance. One of the patients with the severe form had a mutilating palmoplantar keratoderma. Neither employment nor dermatophytosis influenced the severity of the hyperkeratosis in any of these two types. Occurrence of hereditary palmoplantar keratoderma together with other genodermatoses of dermatoses with a polygenic mode of inheritance was also found in this study.