Similar to the GNAT1 phenotype23, patients in the SLC24A1 pedigree presented with lifelong night-blindness, but with very distinctive, albeit mild, symptoms of RP including progressive mid-peripheral visual field loss, early appearance of cataracts and unmistakable pigmentary retinopathy on fundus photography (Fig. 4). This evidence concerns the gene GNAT1 and retinitis pigmentosa 1.