APOE and Alzheimer disease: Although differences in genotype distribution and frequencies of all these genes between patients with AD and control subjects are negligible, except in the case of APOE [39] (Figure 3 and Figure 4), some of them may influence the pharmacogenetic outcome in the treatment of major risk factors for dementia, such as hypercholesterolemia, cardiovascular disorders, and hypertension [39,40,41,42,43].