A DNA methylation study of the amyloid precursor protein gene in several brain regions from patients with familial Alzheimer disease.

Presence of extracellular amyloid plaques is a neuropathological hallmark of Alzheimer disease. Here the authors have compared the methylation status of a CpG-island in the amyloid precursor protein gene (APP) in DNA extracted from the more plaque-vulnerable cortex regions with DNA from the more plaque-resistant cerebellum using material from six familial Alzheimer disease cases. Bisulfite sequencing of a 188 bp fragment in the APP associated CpG-island showed no methylation in any sample, suggesting that APP is not transcriptionally regulated by methylation in any of the investigated brain regions.