Dr. Aguirre is a world-leading Professor of Medical Genetics and Ophthalmology at the University of Pennsylvania School of Veterinary Medicine. His distinguished career in dog health has resulted in life changing medical treatments in the field of ophthalmology for both dogs and humans. Dr. Aguirre's research interests include molecular basis of inherited eye diseases, and developing DNA-based tests for their control. His clinical interest is inherited eye disease and he is the director of the "Inherited Eye Diseases Clinic".
He worked alongside Dr Elaine Ostrander in the first dog genetic mapping project and has also been responsible for the advancement of research into canine eye diseases. His veterinary ophthalmological and gene-therapy research work focuses on inherited diseases of the eye, especially degeneration of the retina in dogs, humans, and other mammals. Since dogs and people share such similar genetic makeup, his identification of retinal disease genes in the dog has also led to the identification of the comparative human retinal disease genes.
To date, Dr Aguirre has identified more than 14 different retinal disease genes that cause inherited blindness in more than 59 breeds of dogs. In 2001, he and his colleagues at Penn were the first to restore vision in blind dogs using gene therapy. He began working with Briards, a breed of sheepdogs predisposed to a form of blindness similar to Lebers Congenital Amaurosis (LCA) in humans. LCA is a group of degenerative diseases of the retina, and is the most common cause of congenital blindness in children. It is an autosomal recessive condition (i.e. when both parents carry the specific genetic mutation, each child has a 25 percent chance of being affected.) Symptoms usually are noticed in early infancy and include loss of vision, light sensitivity, and wobbly eye movement (nystagmus). One type of LCA is caused by a mutation in the RPE65 gene, whose function is to process a type of vitamin A needed to keep light-sensing photoreceptor cells - the rods and cones of the retina - in operating order. The disorder is untreatable and severe, causing blindness early in life. Dr Aguirre and his team set out to replace the non-functioning gene with one that works - and to restore vision.
The dogs were ideal for the new gene therapy because their eyes are similar in size and structure to those of humans. Electroretinography, which measures eye function, was performed on the dogs three months after their minor surgery to inject the replacement healthy gene, but even before the tests confirmed improved vision, animal caretakers knew they could see out of the treated eyes as they started moving around independently by themselves as their sight started to return! One of the dogs, Lancelot, became a media darling when he visited Congress and shook paws with legislators to help increase awareness of the potential of gene therapy. He retained his restored vision throughout the rest of his life.
Following such success in treating this form of canine blindness, the therapy was used on humans with outstanding success and has been transforming the lives of people with forms of genetically caused blindness.**
Dr. Aguirre was born in Cuba but now lives in Philadelphia and is currently involved in research regarding inherited eye diseases among which are progressive retinal atrophy (PRA), and cataracts.
**Dale Turner, a young Canadian in his twenties from Toronto underwent one of the first gene replacement operations in humans in one eye in 2008. Born with LCA, his vision gradually diminished throughout his childhood. At age 11 he could read aloud in front of his school class, but by the following year he couldn’t see well enough to do that and soon after he went completely blind. “I was so scared” he said. “For a child trying to understand his world, it was more than overwhelming.” Assistive technologies helped him read and so continue his education, and he persevered and went on to take a business degree at University in Ontario before then moving on to study law. He said he didn’t want his blindness to stop him getting on with his life but that didn’t mean it hadn’t affected him profoundly.
Following his surgery, which was similar to that performed on Lancelot and the other dogs, he said it took a few days of recovery before he was able to go outdoors…. But when he did, what he saw was spectacular. “I saw blue sky for the first time. I was just standing in disbelief, thinking that the sky was always this blue but I just could never see it. I couldn’t believe it.” He has emailed and thanked all the researchers whose dedication and work resulted in his treatment. He told them “Every morning I wake up and look at the sun rise, and every day as it goes down, and I think these things are so priceless…. and they gave me that gift.”