FAMILIAL ALZHEIMER'S DISEASE

Abstract

Summary: 1. A family was recorded in which two family members, out of a sibship of ten, were investigated in hospital and had the clinical diagnosis of Alzheimer's disease confirmed by post‐mortem examination in both cases. In addition, two sisters, one brother and the mother, were reported to have suffered from a similar illness, and may be considered to have had the same condition.2. Blood grouping was carried out on thirty‐one members of the family, an investigation designed to study genetic linkage. This section of the study is reported by Dr R. R. Race in an appended note.3. The symptomatology of the family members conformed in most aspects with the numerous clinical descriptions, but certain symptoms like motor restlessness and epileptic fits were not prominent. The age of onset was slightly earlier in females than in males, and there was a preponderance of females. The family pedigree suggested a dominant mode of inheritance. The theory of multifactorial inheritance with varying threshold differences in families may explain the differences in manifestation of the disease.4. A further investigation of the hospital records was carried out. Twenty cases of clinically diagnosed Alzheimer's disease and one pathologically verified case were studied. This revealed three more familial cases, and in one of these the diagnosis had been proved to be Alzheimer's disease in one family member on post‐mortem examination.5. The findings of the whole investigation suggested that familial Alzheimer's disease was more common than has been previously stressed, and indicated the need for more detailed studies of affected families.