CRB1 and retinal degeneration: Whereas, in our Crb1 mutant rat studies, 1 μL of a dose of 1 × 1013 gc/mL was injected intravitreally at P5, which might be a too low dose of ShH10Y-hCRB1 or ShH10Y-hCRB2 to slow down the retinal degeneration observed in the Crb1 mutant rats.