MAPT and Alzheimer disease: AD is characterized by the abnormal folding and aggregation of the β amyloid (Aβ) and Tau proteins, which favor the formation of amyloid plaques and neurofibrillary tangles (NFTs), causing brain atrophy with marked cognitive impairment as the disease progresses (Jellinger, 2006; Querfurth and Laferla, 2010).