New hope for people with retinitis pigmentosa
Thousands of people born with a faulty gene which makes them go blind have been offered new hope after a British man underwent the world’s first operation to deliver new DNA to his eyes and restore his sight.
X-linked retinitis pigmentosa is a deteriorating condition which brings a slow and irreversible loss of vision, and which is the leading cause of blindness in young people. Loss of sight occurs because a gene responsible for maintaining the light sensitive cells at the back of the eye is missing half of its DNA code.
According to a report in the Science section of The Telegraph, scientists can now replace the code using a groundbreaking technique which reprogrammes the gene in the lab, then delivers the healthy DNA into the eye, via a harmless virus.
Recently, a 29-year-old man became the first person in the world to undergo the procedure at The UK’s Oxford Eye Hospital and is now recovering.
Robert MacLaren, Professor of Ophthalmology at the University of Oxford, who is leading the trial said: “Changing the genetic code is always undertaken with great caution, but the new sequence we are using has proven to be highly effective in our laboratory studies.
“The genetic code for all life on Earth is made up of four letters – G, T, A and C. In retinitis pigmentosa, however, half of the RPGR gene comprises only two letters – A and G. This makes the gene very unstable and prone to mutations, making it a lead cause of blindness in patients with retinitis pigmentosa. RPGR is vital for the light sensitive cells at the back of the eye.”
Retinitis pigmentosa affects 1 in 4000 people, with symptoms that typically appear between age 10 and 30.
Doctors want to enroll at least 24 more patients in the trial to find out if the technique is safe and effective.