ApoE4 for instance is the most important genetic risk factor for late onset Alzheimer Disease (AD) (Poirier et al., 1993; Leduc et al., 2011; Verghese et al., 2011) with ApoE4 carriers having a 4 to 12-fold increased risk of developing AD when compared to non-carriers (Corder et al., 1993, 1994; Bertram and Tanzi, 2008; Mahley and Huang, 2012a). Here, APOE is linked to Alzheimer disease.