Furthermore, in 4-week-old Hbs1ltm1a/tm1a mice, western blotting revealed the remarkable decrease of rhodopsin levels but not of Opn1sw (Fig. 6C,D), a cone opsin involved in color vision, indicating that the observed retinal degeneration affects mostly rods but not cones at this time point. Here, OPN1SW is linked to retinal degeneration.