MAPT and Alzheimer disease: The National Institute on Aging (NIA) and the Alzheimer's Association (NIA-AA) set a guideline for AD diagnosis and that is termed ATN; “A” stands for Aβ biomarker (amyloid PET or CSF Aβ42); “T” for the tau biomarker (CSF p-tau or tau PET); and “N” for the neurodegeneration biomarker (CSF t-tau, FDG-PET, or structural MRI) (Jack et al., 2016, 2018).