Additionally, a recent study found that CSF ApoE mediated the positive association of APOE ε4 with tau without affecting the inverse relation between APOE ε4 and Aβ (Slot et al., 2019), indicating that CSF ApoE might be involved in AD pathology with mechanisms independent of those of APOE gene on AD pathology. The gene discussed is APOE; the disease is Alzheimer disease.