rs4420638 was not associated with AD with APOE adjustment (model 2: OR, 1.06; 95% CI, 0.96-1.18; P = .24), among ε3 homozygotes (model 3: OR, 1.13; 95% CI, 0.95-1.34; P = .18), or among ε4 homozygotes (model 4: OR, 0.90; 95% CI, 0.56-1.45; P = .66). Here, APOE is linked to Alzheimer disease.