MAPT and early-onset autosomal dominant Alzheimer disease: Classical histopathological findings in the brains of individuals with Alzheimer’s disease include the accumulation of amyloid-beta (Aβ) protein in the neuropil, as well as abnormal phosphorylation (pTau) and aggregation of tau protein within neurons, leading to the formation of paired helical filaments of hyperphosphorylated tau protein, known as neurofibrillary tangles (Achúcarro, 1910).