Our study fills the gaps in previous iRPE studies about patients with BCD (10–12, 15) by examining individual differences in phenotype and response to different AAV-mediated gene therapy treatment strategies among iRPE cells from a diverse pool of 6 patients with BCD of 3 ethnic origins harboring distinct CYP4V2 mutations. The gene discussed is CYP4V2; the disease is Bietti crystalline corneoretinal dystrophy.