Another study on 20,928 participants showed that individuals > 60 years who had APOE Ɛ 4 mutation with KL-VSHET+ genotype had a reduced risk for AD (p = 7.4 × 10− 7, OR = 0.75, 95% CI: 0.67–0.84), and this was more prominent between 60 and 80 years of age (p = 3.6 × 10− 8, OR = 0.69, 95% CI: 0.61–0.79). Here, APOE is linked to Alzheimer disease.