A major study demonstrated that the therapy could restore limited sight to mice born with night blindness, providing the first concrete signs that transplanting nerve cells into the eye can bestow moderate levels of vision. Although the treatment is a long way from being trialled on humans, the "landmark" study offers hope to hundreds of thousands of people suffering from eye conditions like macular degeneration, which affects 15 per cent of over-75s and is the most common form of blindness. While similar treatments involving stem cells have reached the more advanced stage of human trials, the new approach is the first to successfully restore sight using nerve cells which are sensitive to light. Researchers from University College London injected 200,000 immature versions of cells known as rod-photoreceptors, taken from the eyes of newborn healthy mice, into mice with a genetic condition that made them blind in the dark. Some of the cells developed nerve connections which enabled the mice to navigate their way through a maze in low light.
