Retinitis pigmentosa, a genetic condition affects 1 in 4,000 people in the world.
A rare genetic disorder that hampers people's vision gradually, called retinitis pigmentosa affects 1 in 4,000 people in the U.S. and the world. But now a new treatment using gene replacement therapy will probably make this condition a thing of the past. The first person to get the treatment in Canada is a boy identified only by his first name, Sam according to CTV. He was diagnosed with the disorder right after birth. The 8-year-old was not able to see the sky on a cloudy day or make out shapes in the dark. Sam told the channel, “Sometimes you have to walk in the night and I couldn’t see things and you bump into things.” Sam was not able to do simple tasks such as spotting and picking up his shoes from the floor, wearing his clothes and it got worse with age.
But after the treatment, Sam is able to do many things including one he desired the most when his vision was deteriorating - star-gazing. “I never saw stars before. And I also never saw airplanes flying at night.” He received treatment last year in the U.S. since it was not available in his country then. Sam's mother, Sarah Bannon said the results of the treatment were immediate. “About a week later, I noticed he could get dressed by (himself). He could get his shoes on by himself, independently,” she said. His improvements have been rapid and have continued over the course of the year since he got the treatment. “He is so much more confident. Like getting dressed by himself, matching clothes, doesn’t have to have things enlarged. Being able to (see), even when it’s dark outside, no lights on and it is a cloudy day. He would have to, at school, keep the lights on," said Bannon.
So happy for him and his family, and the scientists behind the technique, doctors and nurses involved too :)— Jen Summers (@Ari1Ava2Mom3) October 15, 2020
"Now he is able to function as a normal child,” she added. Canada has now approved this gene replacement therapy for the disorder and more people are waiting in line for the treatment in the country. At the Sick Kids Hospital, 29 children with the disorder eagerly wait to also avail of the benefits of the treatment. While the therapy also works for adults but doctors suggest, the earlier it's done the better. Explaining the effects of the disease, Dr. Elise Heon, from the hospital said, “You lose perception of light. You end up in darkness and (it’s) slowly progressive, it's relentless, your visual field shrinks and shrinks and shrinks and shrinks. It's a huge deal, because for these patients before, there’s no treatments.” Heon highlighted meeting a pair of siblings with the condition and said, “They're 10 years old, and they're losing their vision.”
The degenerative eye disease retinitis pigmentosa may soon have a gene therapy. Mice injected with a virus carrying the gene CX3CL1 had prolonged cone survival and better visual acuity, according to research published this week. In PNAS: https://t.co/sexUfnfL6h pic.twitter.com/K0nUexdkje— PNASNews (@PNASNews) May 1, 2019
She added, "If we do nothing, they're just going, fine, they'll just end up with no light reception. So for the first time (we were) able to say, well, actually we need to have a discussion. And it was just, it was priceless.” The therapy was developed by a U.S. based drug company called Spark Therapeutics and named Luxturna. The National Eye Institute explains what exactly happens to a person with the disorder on its website: "RP is an inherited disorder that results from harmful changes in any one of more than 50 genes. These genes carry the instructions for making proteins that are needed in cells within the retina, called photoreceptors. Some of the changes, or mutations, within genes are so severe that the gene cannot make the required protein, limiting the cell's function."
"Other mutations produce a protein that is toxic to the cell. Still other mutations lead to an abnormal protein that doesn't function properly. In all three cases, the result is damage to the photoreceptors," it added. The treatment involves placing a copy of the healthy gene into viruses that are inactivated according to CTV report. This is then injected into the retina. The necessary protein to convert light into an electrical signal in the retina is then produced in the cells to prevent the progression of the disorder and the development of healthy vision.