GDNF (glial cell line–derived neurotrophic factor), which protects photoreceptor cells in the eye (Read SP et al. Mol Ther. doi:10.1038/mt.2010.167 [published online August 10, 2010]). Injection of the therapeutic nanoparticle into the subretinal space in the mouse eye significantly reduced lightinduced apoptosis of the photoreceptor cells and improved eyesight in the mice temporarily. As Kumar-Singh noted, the majority of retinal diseases, including retinitis pigmentosa and age-related macular degeneration, have a common pathway of photoreceptor loss through apoptosis, and the disease model of retinal degeneration they used is a general one, rather than being specific for one disease. In addition, the use of the gene for a growth factor makes this approach more generic and potentially applicable to a wide spectrum of retinal diseases, he said. Kumar-Singh and his team are working to improve the efficiency and longevity of this approach before moving into clinical studies.