SMN1 and inherited retinal dystrophy: Currently, there are three approved AAV gene-therapies (Table 1): AAV1-LPLS447X driven by cytomegalovirus (CMV) promoter for treatment of Lipoprotein Lipase Deficiency (LPLD) in 2012 [27]; AAV2-RPE65 driven by a CMV/Chicken-β-actin (CβA) hybrid promoter for treatment of inherited retinal dystrophy (RD) caused by biallelic RPE65 dysfunction in 2017 [28–30]; and self-complementary AAV9-SMN1 driven by a CMV/CβA hybrid promoter for treatment of spinal muscular atrophy 1 (SMA1) in 2019 [31].