Moreover, the prospective cohort, Manhattan study found that higher HDL-C levels (>55 mg/dL) were associated with a decreased risk of both probable and possible AD (hazard ratio, 0.4; 95% confidence interval, 0.2–0.9; p = 0.03), also after adjustment for age, sex, education, ethnic group, and APOE4 genotype [11]. The gene discussed is APOE; the disease is Alzheimer disease.