Alzheimer's disease (AD), the major cause of dementia, is characterized by the aberrant folding of the protein tau, leading to its intracellular and extracellular accumulation and to β-amyloidosis seen as extracellular deposits of β-amyloid (Aβ) in the brain parenchyma and around cerebral blood vessels [1-8]. Here, MAPT is linked to early-onset autosomal dominant Alzheimer disease.