Man Saved From Blindness By Gene Therapy
Virus used to deliver gene therapy into retina.
Jan. 20, 2014— -- At age 10 Nick Tuftnell knew he was going to end up blind after being diagnosed with the genetic condition choroideremia.
The condition leads to the death of light-absorbing cells in the eye. The cells die because of a mutated gene in certain ocular cells, which eventually leads to blindness.
“I knew my granddad had it. I remember seeing him in the latter stages of life and he was completely blind,” said Tuftnell, now 38.
After his condition was confirmed, Tuftnell said he had nothing to do but wait for his eyesight to slowly dim and darken over time.
“All the doctors could say is ‘Your son is going to go blind, see you later,’” said Tufnell of receiving his diagnosis.
As he grew older his eyesight has diminished to the point where he can no longer drive due to poor peripheral vision and has severe difficulty moving around at night.
“I can’t walk around at night, it’s that bad,” said Tuftnell. “I don’t have any peripheral vision…eventually it’ll get like I’m looking through toilet rolls.”
Tuftnell said his doctors estimated that he had around “ten years of useful vision left.”
However, two years ago Tuftnell took part in a groundbreaking study where gene therapy was used to treat his deteriorating condition.
The results of the study were published last week in the Lancet Medical Journal.
Tuftnell was one of six patients in a study from the University of Oxford, who underwent gene therapy to help stop the deterioration caused by choroideremia. To help the dying ocular cells, doctors injected working versions of the gene into Tuftnell's eye. The gene can then start to “fix” the cells by patching missing genetic data.
Virus particles were used to deliver the genes in fluid behind the retina.
Dr. Robert MacLaren, professor of ophthalmology at the University of Oxford and lead author of the study, said all the patients had choroideremia, which would eventually have left them blind.
“The key thing about our study that is new is that we’ve gone in before they lost their visual acuity,” said MacLaren, who pointed out that two patients had 20/20 vision before the surgery. “The best way to fix [cells is to] put in the missing gene before they die.”
MacLaren said he warned participants that undergoing the operation for the study could mean their vision was more impaired than before the surgery.
“I talked to them and said you’re going to be like one of the first astronauts,” said MacLaren.
The treatment included an operation that would temporarily involve detaching Tuftnell’s retina. It’s a procedure that is done only in the rarest of circumstances because it can result in permanent damage to the patient’s eyesight.
Tuftnell said after meeting with MacLaren and the other researchers he decided to take the risk.
An additional factor that led Tuftnell to want to try the surgery was the fact that he had just lost his wife to cancer six months earlier.
Tuftnell said he felt he had to try, “any chance I’ve got of trying to save" his vision to stay active with his now 5-year-old son Theo.