RPE65 and Leber congenital amaurosis: As leading example, treatment of RPE65-dependent Leber congenital amaurosis (LCA) by subretinal injection of adeno-associated viral vectors (AAV) has shown promising results in Phase 3 clinical trials and is expected to reach the clinic soon (Schimmer & Breazzano, 2015; Spark Therapeutics Press Release, 2016).