APOE and Alzheimer disease: This biology is likely reinforced by the depletion of PI precursors, notably PI(16:0/20:4), PI(18:0/20:4), PI(16:0/22:6), and PI(18:0/22:6) observed in ApoE-deficient and AD transgenic mice (Igbavboa et al., 2002; Chan et al., 2012).