PROM1 and Stargardt disease 4: Prom1-associated macular dystrophy, also known as Stargardt disease 4 (STGD4), has clinical and pathophysiological features similar to ABCA4-related Stargardt disease 1 (STGD1) and the atrophic (dry) form of age-related macular degeneration (AMD), where abnormal cytotoxic lipofuscin bisretinoid accumulation triggers degeneration of macular rods, cones, and retinal pigment epithelial (RPE) cells [14,15,16].