In 2008, a team of scientists funded by the National Eye Institute (NEI), a part of the National Institutes of Health, reported major progress in the treatment of an inherited form of progressive blindness using gene therapy. The team now reports that although treatment improved eyesight, cells in the eye crucial for vision continued to diminish in number. This new finding suggests a need for a combination therapy that restores vision and protects the eye's cells. The findings are published in the January 21 early online issue of Proceedings of the National Academy of Sciences. Read more from NEI.