DNA Damage does not Correlate with Amyloid-beta-Plaques and Neurofibrillary Tangles in Familial Alzheimer's Disease Presenilin-1 [E280A] Mutation.

Recent studies have shown that the missense mutation in presenilin-1 [E280A] increases deposition of amyloid-beta (Abeta) and neurofibrillary tangle (NFT) formation. Indeed, we only observed 10 out of 48 FAD brain sections displaying TUNEL (+) labeling, and none with the classical apoptotic morphology. These results may indicate that DNA fragmentation is not a generalized phenomenon in early-onset FAD PS1 [E280A] patients or that neuronal cells are dying by a different mechanism of cell death. Taking together these findings suggest that Abeta and NFTs are not per se a causative factor to damage neuronal cells but their damage could be more related with individual neuronal vulnerability and brain aging