Using AAV8 (Y447, 733F + T494V)-IRBP/GNAT2-Cnga3, we obtained a more robust rescue than using AAV2 (Y272, 444, 500, 730F + T491V) or AAV8 (Y447, 733F) vectors in cpfl5 mouse, a spontaneous animal model of achromatopsia with a Cnga3 mutation. The gene discussed is CNGA3; the disease is achromatopsia.