MAPT and Alzheimer disease: Classic symptoms of AD start when the two main lesions in the CNS (the accumulation of beta-amyloid peptides (Aβ), with the formation of amyloid plaques [93] followed by the hyperphosphorylation of Tau protein, which determines the formation and accumulation of neurofibrillary tangles (NTF) [94]) affect neurons involved in memory, cognition, and neurogenesis.