APOE and neurodegenerative disease: A recent study used APOE-TR mice to examine the interactive effects of sex, APOE and age on brain transcriptomic profiles, and found that these variables interactively influenced the expression of genes in the unfolded protein response pathway (Zhao et al., 2020b), a response to endoplasmic reticulum stress implicated in the etiology of neurodegenerative diseases (Scheper and Hoozemans, 2015).