APP and Alzheimer disease: For instance, mutations in genes encoding amyloid precursor protein (APP), presenilins (PSEN1 and PSEN2) or microtubule associated protein tau (MAPT) have been overexpressed in animals to make Alzheimer’s disease (AD) mouse models, which are characterized by the production and accumulation of amyloid-β into plaques or of hyperphosphorylated tau into neurofibrillary tangles [25], [26].