This model carries the two wild-type murine Rho alleles as well as an undefined number of transgenic alleles with the p.Pro347Ser variant and has a 1:1 ratio of transgene to endogenous opsin mRNA, which causes severe retinal degeneration by postnatal day (P) 30, as seen by electroretinogram responses and loss of outer nuclear layer (ONL) thickness.14 This evidence concerns the gene RHO and retinal degeneration.