Amyloid-β precursor protein (AβPP), presenilin 1 (PSEN1), and presenilin 2 (PSEN2) genes have been strongly implicated in early onset Alzheimer’s disease (EOAD), particularly familial EOAD, which comprise less than 5% of Alzheimer’s cases (15). This evidence concerns the gene PSEN2 and early-onset autosomal dominant Alzheimer disease.