There could be a new ending to the children's song "Three Blind Mice," because a cell transplant has restored sight in totally blind mice. This may give new hope to people with retinitis pigmentosa, an inherited eye disease where cells in the retina degenerate and die. In research led by the Nuffield Laboratory of Ophthalmology at the University of Oxford, researchers transplanted rod precursor cells (cells that are destined to become one of the types of photosensitive cells in the eye) into totally blind mice with no light-sensing photoreceptors. The transplanted cells restored the light-sensitive layer of the retina, giving the mice back at least some level of sight. But it's not clear yet how good this sight is, and more research is needed--so the three blind mice should keep their wits about them a little longer. Abstract | Article