Stage A corresponds to positive amyloid PET and negative tau PET (A+T2); tau PET with uptake only in the medial temporal region (A+T2MTL+) is equivalent to stage B; tau PET with moderate neocortical uptake (A+T2MOD+) is stage C; and high tau PET high neocortical uptake (A+T2HIGH+) represents stage D. So, for staging AD, tau PET is currently the only available biomarker4. Here, MAPT is linked to Alzheimer disease.