Familial hypotrichosis of the scalp. Autosomal dominant inheritance in four generations.

A Danish family spanning four generations exhibited familial hypotrichosis of the scalp, characterized by gradual hair loss beginning between ages 6 and 17, leading to almost total scalp alopecia by ages 14 to 21. Out of 22 family members, 9 were affected. The condition showed no associated ectodermal defects and was identified as non-scarring alopecia with features similar to androgenetic alopecia. The inheritance pattern was consistent with autosomal dominant transmission.