See Blind Mice: Algae gene makes sightless eyes sense light
Scientists have prompted mouse-eye cells that aren’t normally light sensitive to respond to light. This strategy could lead to new treatments for retinitis pigmentosa and related diseases, which cause blindness in 1 in 3,000 people worldwide.
These diseases occur when the retina’s light-sensing cells die. Called rods and cones, these cells—when healthy—convert light into an electrical signal. That signal then passes to nearby cells and eventually reaches the brain, where it’s interpreted as vision. If rods and cones die, they aren’t replaced.