Dose of the APOE ε4 allele was associated with a strong deleterious effect on the hazard of AD (discovery HR: 2.50 [95% CI: 2.43–2.57], p < 2 × 10−16; replication HR: 2.50 [95% CI: 2.41–2.59], p < 2 × 10−16). This evidence concerns the gene APOE and Alzheimer disease.