Characterization of the kindred of Alois Alzheimer's patient with plaque-only dementia.

We describe the kindred of Alois Alzheimer's second published patient (Johann F.) with the brain pathology typical of a subgroup of Alzheimer disease called "plaque-only type." The genealogic records of the kindred extend back to 1670. We constructed a family tree of 1403 individuals and identified 4 living demented members of the Johann F. kindred. The pedigree is consistent with an autosomal dominant trait. The analyses of known dominant dementia genes (APP, PS1, PS2, PRNP, and BRI) failed to reveal mutations in the proband. Further examination of this family might yield new insights into the genetics of Alzheimer disease.

[Familial plaque-only Alzheimer's disease in the Rottal-Inn and Passau counties]. / Familiäre Plaque-only-Alzheimer-Krankheit in den Landkreisen Rottal-Inn und Passau--Genetisch-genealogische Alzheimer-Forschung.

We describe the kindred of Alois Alzheimer's second patient, who died from plaque-only Alzheimer's disease (AD) in 1910. There is a neuropathologically defined subtype of AD without or only few tangles. This plaque-only form is found in about 6 % of autopsied cases of AD. We recruited of AD patients with age of onset before 70 years from the Rottal-Inn and Passau counties in Bavaria and extended a kindred with familial dementia using genealogies deduced from historic parish records. 1247 individuals were documented genealogically. In the maternal branch of the kindred we documented 40 deceased individuals with possible Alzheimer's disease, whereas other branches of the family had no suspicious entries. We conclude, that there is a familial predisposition to dementia with variable age of onset between 36 and 80 years of age in the kindred of Johann F.