The index-patient is marked by an arrow. Three males IV/1, IV/2 and V/1 have the mutation. A total of six females III/2, III/3, III/5, III/20, III/21 and IV/V were shown to be carriers. In subjects marked by a star the mutation was excluded. The rest of the family members did not participate in the study. The number of children and their sexes are not known in IV/9–IV/16.