MAPT and early-onset autosomal dominant Alzheimer disease: Alzheimer’s disease(AD) is the most common form of dementiaamong elderly individuals worldwide.1,2 Several behavioralabnormalities, including memory loss, cognitive decline, sleep disorders,and neuropsychiatric problems, are indicative of AD.3−5 From a molecular perspective, the histopathological hallmarks ofAD include the formation of intracellular neurofibrillary tangles(NFTs)6−9 made up of abnormal depositions of misfolded microtubule-associatedprotein-tau isoforms and extracellular senile plaques made up of misfoldedand aberrantly accumulated amyloid-beta (Aβ) peptides10−14