MAPT and Alzheimer disease: The current recommendations for AD diagnosis include tau/amyloid cerebrospinal fluid (CSF) and positron emission tomography (PET) imaging (Dubois et al., 2021), but there is a still unmet need for easily accessible and objective biomarkers either for biological definition of AD and its prodromal phase, the amnestic mild cognitive impairment (aMCI), as well as for stratifying the risk of conversion from aMCI to AD.