According to the study conducted by Farrer et al. (1997), the association between APOE ε4 and AD in Japanese people (ε3/ε4: OR 5.6, 95% CI = 3.9–8.0, ε4/ε4: OR 33.1, 95% CI = 13.6–80.5 relative to ε3/ε3) was higher than in Caucasian people (ε3/ε4: OR 2.7, 95% CI = 2.2–3.2, ε4/ε4: OR 12.5, 95% CI = 8.8–17.7), while the association was lower among African Americans (ε3/ε4: OR 1.1, 95% CI = 0.7–1.8, ε4/ε4: OR 5.7, 95% CI = 2.3–14.1) and Hispanics (ε3/ε4: OR 2.2, 95% CI = 1.3–3.4, ε4/ε4: OR 2.2, 95% CI = 0.7–6.7) (Farrer et al., 1997). This evidence concerns the gene APOE and Alzheimer disease.