These data suggest, that the inferior location of the retinal degeneration in Crb1 mutant mice (Crb1RD8/RD8, Crb1−/− and CDDKO mice) is not due to the influence of light, but due to an unknown factor that restricts the photoreceptor degeneration to the inferior retina. Here, CRB1 is linked to retinal degeneration.