Alzheimer’s disease (AD)is the most prevalent cause of dementia among elderly people withunknown etiology.1 The cytopathologic hallmarksof AD are the extracellular amyloid-β protein (Abeta) and intracellularneurofibrillary tangles, which lead ultimately to profound neuronaltoxicity and tissue atrophy.2 Particularly,the Abeta proteins with full-length amino acid residues 1–40and 1–42 have been the center of research focus for severaldecades. This evidence concerns the gene APP and dementia.