APP and Alzheimer disease: Transgenic mouse models incorporate a variety of promoters to overexpress familial AD-associated mutations in APP and PS1, potentially leading to variability in Aβ expression, which may partially account for the inter-mouse variability in our results (Chang and Suh, 2005; Mitani et al., 2012; Nicolas and Hassan, 2014; Kerridge et al., 2015; Nhan et al., 2015; Willem et al., 2015).