APOE and Alzheimer disease: Although it is well-established that APOE4 is the strongest genetic predictor of sporadic AD and is associated with early amyloid deposition rate and burden (Corder et al., 1993; Ossenkoppele et al., 2015; Ridge et al., 2016; Lim et al., 2017; Ge et al., 2018; Mishra et al., 2018; Toledo et al., 2019; Insel et al., 2021), a growing body of evidences suggests that APOE4 is also involved in tau pathology (Table 1).