MAPT and early-onset autosomal dominant Alzheimer disease: Alzheimer's disease (AD) is histopathologically characterized by the deposition of the amyloid-β peptide (Aβ) [1] as well as by the generation of intraneuronal neurofibrillary tangles (NFTs) consisting of abnormally phosphorylated tau (τ) protein (p-τ) [2].