APOE and Alzheimer disease: The effect of APOE genotype on amyloid deposition has been shown previously, including in middle-aged and older cognitively healthy adults, as well as patients with L-MCI and AD (Drzezga et al., 2009; Shaw et al., 2009; Morris et al., 2010; Fleisher et al., 2011; Tosun et al., 2011).