Therefore, new criteria for diagnostic research have been proposed with the aim to incorporate supportive biomarker information, for example, CSF Aβ and tau monomer concentration, glucose and amyloid imaging using positron emission tomography (PET), and magnetic resonance spectroscopy (MRS) for the detection of brain atrophy to allow a more sensitive and specific diagnosis of AD in preclinical stages, that is, when symptoms are not yet apparent [17, 18]. This evidence concerns the gene MAPT and Alzheimer disease.