The APOE gene, encoding apolipoprotein E (APOE), is a major genetic risk factor for AMD, with the APOE2 allele conferring increased risk and APOE4 conferring reduced risk, in comparison to the wildtype APOE3. Paradoxically, APOE4 is the main genetic risk factor in Alzheimer’s disease, a disease with features of neuroinflammation and amyloid-beta deposition in common with AMD. The gene discussed is APOE; the disease is age-related macular degeneration.