Researchers at Michigan State University believe that gene therapy used to treat an inherited form of total color blindness in dogs could also be used in treating the same condition in humans along with other eye disorders. The researchers worked upon the theory that certain photoreceptor cells in the eyes known as "cones" were too worn out in older dogs to effectively process light and color. Dogs between one and three years of age were involved in the study and all had acromatopsia (color blindness). Researchers treated some of the dogs with CNTF protein which is necessary for healthy cells. Those dogs received a dose that was high enough to partially destroy the photoreceptors and cause new cell growth. The researchers then replaced the gene associated with the condition. All of the dogs who received this treatment responded to it. While researchers are encouraged by these study results, they note that success in animal research does not necessarily mean success in humans.