| First Author | Chang B | Year | 2024 |
| Journal | MGI Direct Data Submission | Mgi Jnum | J:349874 |
| Mgi Id | MGI:7660533 | Citation | Chang B (2024) The retinal degeneration 25 (rd25) mutation. MGI Direct Data Submission |
| abstractText | The retinal degeneration 25 (rd25) heritable mutant phenotype was discovered in our ocular phenotypes screening program in August 2020 in strain B6.129S2(Cg)-Ramp1tm1.1Tsuj/WkinJ (JAX Stock No. 031560) that presented with late-onset progressive retinal degeneration at 5 months of age (Figure 1B, 1C and 1D), but the fundus was normal at 3 month of age (Figure 1A). We obtained more breeding pairs at different ages of B6.129S2(Cg)-Ramp1tm1.1Tsuj/WkinJ (when this strain was removed from the shelf in 2022) and we discovered that this strain was fixed homozygous for the rd25 mutation. We mated the mutant from Stock No. 031560 with C57BL/6J and all F1 mice had normal retinas. The retinal degeneration phenotype was recovered in the F2 generation, from which siblings were mated to generate a homozygous line, B6.Cg-rd25/Boc (JAX Stock No. 036969). Mice homozygous for rd25 exhibit a normal retina at 3 months of age (Figure 1A) and begin to show retinal degeneration at 5 months of age (Figure 1B) in OCT. Histology and OCT at 10 months of age showed ~30-40% photoreceptor loss. Electroretinograms (ERG) of rd25/rd25 mice show normal rod ERG responses at 3 months of age, abnormal rod ERG responses (lower ERG) at 5 and 10 months of age, but the cone ERG responses were not much changed within the same time frame (Figure 1 ERGs). A linkage cross to DBA/2J followed by a backcross to B6.Cg-rd25/Boc then showed this spontaneous mutation to be an autosomal recessive mutation that mapped to Chromosome 14 between D14Mit62 and D14Mit234; the best candidate gene would be retinitis pigmentosa GTPase regulator interacting protein 1 (Rpgrip1). |
