Notably, accumulating evidence supports that plasma p-tau, the most promising biomarker for AD, shows outstanding performance in differential diagnosis, in relation to other biomarkers, neuropathology, prediction, progression monitoring, and prognosis (Mielke et al., 2018; Janelidze et al., 2020, 2021; Palmqvist et al., 2020). This evidence concerns the gene MAPT and Alzheimer disease.