The hallmark neuropathological features of AD are accumulation of amyloid-β 42 (Aβ42) in plaques and neurites, and of phospho-Tau (pTau) in neurofibrillary tangles and dystrophic neurites, both of which are the basis for the current National Institute on Aging-Alzheimer’s Association (NIA-AA) guidelines for the neuropathological assessment of AD [2]. The gene discussed is MAPT; the disease is Alzheimer disease.