However, in some cases, these impairments develop into Alzheimer's disease (AD), a progressive neurodegenerative disorder that is neuropathologically characterized by extracellular senile plaques, formed by amyloid-β (Aβ) accumulation and intracellular neurofibrillary tangles, composed of a hyperphosphorylated microtubule-associated protein called tau (Ashe and Zahs, 2010; Tarawneh and Holtzman, 2012). This evidence concerns the gene MAPT and Alzheimer disease.