MAPT and Alzheimer disease: To date, AD can only be diagnosed post-mortem, through two characteristic neuropathological lesions in the brain: senile plaques, consisting of β-amyloid protein oligomers aggregates (Aβo, residues 1–40/42), and intracellular neurofibrillary tangles (NFT), constituted of abnormally hyperphosphorylated tau protein accumulation predominantly in hippocampal and cortical regions.