MAPT and Alzheimer disease: Numerous biochemical and genetic biomarkers, e.g., increased cerebrospinal fluid (CSF) tau, phosphorylated tau and ubiquitin levels, low CSF Amyloid-β (Aβ42) concentration, and apolipoprotein E (ApoE) ε4 allele, have been proposed to detect AD onset and predict conversion of MCI and normal control (NC) to AD with high specificity and sensitivity (Trojanowski et al., 2010; Kandimalla et al., 2011, 2013, 2014; Andreasson et al., 2014).