The finding that mutations in a CerKL gene are associated to a variant of autosomal recessive retinitis pigmentosa (Tuson et al., 2004), and to Cone-rod dystrophy (Littink et al., 2010; Birtel et al., 2018) brought huge expectations to the field, as it associated sphingolipid metabolism and retinal degeneration. This evidence concerns the gene CERKL and Rod-cone dystrophy.