MAPT and Alzheimer disease: Alzheimer’s disease (AD) is an age-related neurodegenerative disease with progressive memory decline and cognitive dysfunction, which is pathologically characterized by extracellular deposition of β-amyloid (Aβ) and intracellular neurofibrillary tangles (NFT) of hyperphosphorylated tau, accompanied by neuroinflammation, neuronal, and synapse loss (Long and Holtzman, 2019; van der Kant et al., 2020; Knopman et al., 2021).