Several studies41–44 have suggested, analogous to FHR-1 and FHR-3, that complement factor H-related 4 protein (FHR-4) can compete with FH/FHL-1 to alter AP activation and, therefore, that modulation of FHR-4 may be an attractive AMD therapeutic strategy. This evidence concerns the gene DHCR7-DT and age-related macular degeneration.