MAPT and early-onset autosomal dominant Alzheimer disease: Alzheimer’s disease (AD) is a pernicious condition of the aging population that leads to progressive degeneration of brain function, whose characteristic anatomopathological hallmarks, firstly described by Alois Alzheimer, remain the senile plaques and neurofibrillary tangles which consist of beta-amyloid peptides and hyperphosphorylated Tau proteins (Querfurth and LaFerla, 2010).