RPGRIP1 and retinitis pigmentosa 1: RPGRIP1 variants have been reported to cause IRD, including retinitis pigmentosa (RP; #268000), cone–rod dystrophy (CRD; #120970), LCA, and pigmented paravenous retinochoroidal atrophy (PPRCA), and genetic and clinical data have been accumulated [7,8,9,10,11,12].