MAPT and Alzheimer disease: The two major histopathological hallmarks of AD are the formation of amyloid-beta (Aβ) peptides containing amyloid plaques and neurofibrillary tangles (NFTs) composed of altered tau proteins; these are accompanied by a progression in neuronal atrophy and the loss of neurons and synapses, the latter of which correlates best with cognitive impairment in the AD patient [13,14,15,16,17].