MAPT and Alzheimer disease: Several hypotheses have been proposed regarding the pathogenesis of AD, with the most widely accepted mechanisms involving the excessive accumulation of beta-amyloid (Aβ) outside neurons and the aggregation of hyperphosphorylated tau protein within neurons, resulting in the formation of neurofibrillary tangles (NFTs) (Du et al., 2018; Scheltens et al., 2021).