APOE and early-onset autosomal dominant Alzheimer disease: Finally, in addition to its implication in lipoprotein metabolism and cardiovascular disease, ApoE exerts pleiotropic roles in Alzheimer's disease (Shi et al., 2017; Yu et al., 2014), immunoregulation (Braesch-Andersen et al., 2013) and cognition (Davies et al., 2014).