MAPT and Alzheimer disease: AD is considered a multifactorial pathology, characterized by selective neuronal death, failure in cholinergic neurotransmissions, and two main classical pathologic hallmarks, i.e., senile plaques formed by extracellular deposits of amyloid-β peptides, and intracellular neurofibrillary tangles (NFTs) of hyperphosphorylated tau protein (Serrano-Pozo et al. 2011; Guo et al. 2020; Sharma et al. 2019).