just a couple of monkeys

Science Colour blindness cured (albeit in just a couple of monkeys so far):

"We've added red sensitivity to cone cells in animals that are born with a condition that is exactly like human color blindness," said William W. Hauswirth, Ph.D., a professor of ophthalmic molecular genetics at the UF College of Medicine and a member of the UF Genetics Institute and the Powell Gene Therapy Center. "Although color blindness is only moderately life-altering, we've shown we can cure a cone disease in a primate, and that it can be done very safely. That's extremely encouraging for the development of therapies for human cone diseases that really are blinding."

When I was at school, a chemistry teacher said that I knew he wasn't a genius when someone had to tell him he was colour blind -- he thought that a genius would be able to work it out for themselves.