MAPT and early-onset autosomal dominant Alzheimer disease: Alzheimer’s disease (AD) is a multifactorial disorder influenced by a variety of genetic and environmental factors.1 The disease is characterized by the accumulation of misfolded, insoluble protein aggregates, composed primarily of amyloid-β (Aβ) peptide (plaques) and phosphorylated tau protein (forming neurofibrillary tangles (NFT)) in the brain 2,3, which leads to the insidious onset and gradual disruption of cognitive and behavioral functions,3,4,5.