Chromosome aneuploidy in Alzheimer's disease

Lymphocyte chromosomes were examined in 20 women with Alzheimer's pre-senile dementia, 42 non-demented women of similar age and 31 women 15-20 years older than the Alzheimer patients and who were not demented, living independently in the community. Increased chromosome aneuploidy was found in Alzheimer's disease compared to age-matched controls, and this aneuploidy was of a similar nature and degree as that observed in controls 15-20 years older than the Alzheimer patients, though in this latter group there was an increased loss of chromosomes. No single chromosome was preferentially affected in Alzheimer's disease. Because similar chromosome aneuploidy was found in females with Alzheimer's disease and in senescence in the absence of dementia, the 'premature ageing' hypothesis of Alzheimer's disease was preferred rather than the hypothesis that chromosome aneuploidy and dementia arise on the basis of the same biochemical defect.