MAPT and Alzheimer disease: For the research purposes, the AD diagnosis requires the evidence of: 1) amyloid deposition in the autopsy study, low b-amyloid concentrations in cerebrospinal fluid (CSF), or b-amyloid deposition in positron emission tomography; and 2) neuro-degeneration in the autopsy study, high concentrations of phosphorylated Tau in CSF, or pattern of EA atrophy in the cerebral images.55-57 However, amyloid and tau biomarkers are not required in usual clinical practice.