However, apart from the c.2991+1655A>G mutation in CEP290 previously reported to be present in 20% of patients with Leber congenital amaurosis (LCA) and RPGR in male RP patients [6], [7], there is no major mutation or disease gene for RP and LCA, and clear-cut genotype-phenotype correlations are largely lacking, which prevents efficient targeted Sanger sequencing. Here, RPGR is linked to retinitis pigmentosa 1.