In APOE-ε4 non-carriers, the AUC values of the bilateral caudate nucleus and the right putamen in the AD group were (Right caudate nucleus; AUC, 0.756; 95% CI: 0.60–0.91; P = 0.010), (Left caudate nucleus; AUC, 0.737; 95% CI: 0.57–0.91; P = 0.018), and (Right putamen; AUC, 0.74; 95% CI: 0.56–0.92; P = 0.016) (Figure 3C), and the AUC value of the right caudate nucleus in the MCI group was (AUC, 0.762; 95% CI: 0.60–0.93; P = 0.010) (Figure 3D). The gene discussed is APOE; the disease is Alzheimer disease.