MAPT and early-onset autosomal dominant Alzheimer disease: Alzheimer’s disease (AD) is a progressive neurodegenerative disorder that is histopathologically characterized by the deposition of extracellular senile plaques containing amyloid-β (Aβ) protein [1], as well as the intracellular accumulation of so-called neurofibrillary tangles (NFTs) consisting of hyperphosphorylated protein tau [2].