PROM1 and Cone rod dystrophy: Of note, the few cones that were situated in the putative outer nuclear layer displayed an abnormal bulbous OS structure upon the PROM1-PMO treatment, indicating a higher cone sensitivity to PROM1 exon 4 skipping and/or reduced Prominin-1 expression, in accordance with the reported macular phenotypes [17–20] or cone-rod dystrophies [15, 16, 44, 45] associated with PROM1 mutations.