In addition, diverse phenotypes of retinal degeneration in Mdm1−/− mice appeared much earlier than in arrd2 mice, with a more rapid progression: OS fragmentation was observed 7 weeks in the Mdm1−/− mice vs. 9 months in the arrd2 mice; complete loss of ONL and ERG response was observed at 35 weeks in the Mdm1−/− mice vs. 22 months in the arrd2 mice. This evidence concerns the gene SAXO6 and retinal degeneration.