In 2009, Dr. Jean Bennett and his team from Albert Maguire of the University of Pennsylvania School of Medicine injected a benign virus carrying a connected copy of an essential gene into a teenage boy’s retina. This patient had lost vision due to a genetic disorder called “Leber’s Congenital Amaurosis (LGA).
The result was improved vision as the gene therapy enabled the body to make new rods and cones (which normally are irreplaceable once lost).
Other young patients given the same procedure also were able to see better. This remarkable procedure is in a Phase I clinical trial, published in Lancet.