Over the years, various blood p-Tau variants (i.e. p-Tau217, p-Tau181, p-Tau231, p-Tau205, p-Tau202) [7, 8]10– [12] have been measured but among those variants, p-Tau217 has emerged as one of the most promising blood-based biomarkers (BBMs) of AD [8, 13–15]. Here, MAPT is linked to Alzheimer disease.