Owing to its essential function in the visual cycle, mutations in ABCA4 are also associated with retinitis pigmentosa-19, cone-rod dystrophy type 3, early-onset severe retinal dystrophy, fundus flavimaculatus, and other macular degenerative diseases (46, 51, 57, 58, 59, 60, 61, 62, 63). This evidence concerns the gene ABCA4 and Stargardt disease.