Abstract
In Sweden, more than 250 cases of hereditary macular degeneration (HMD), inherited as an autosomal dominant trait and consistent with Best''s disease, have been traced to 1 gene source in the 17th century. In this large material an apparently homozygous father was found who was aged 56 and had 11 affected children. One of the children, aged 24, did not show any macular degeneration, but nevertheless she was considered to be a carrier of the HMD gene because she had pathological EOG[electrooculogram]-values. The great variations in expressivity of the disease in the 11 children reflected what has been found as a rule in large Swedish families with HMD. The homozygotic stage did not seem to differ in clinical appearance from the heterozygotic.