Gene therapy restores Ontario man’s vision
Published Tuesday, July 31, 2012 8:46AM EDT
Last Updated Tuesday, July 31, 2012 8:50AM EDT
Dale Turner remembers the day his view of the world changed, literally, thanks to a groundbreaking clinical trial that partially restored his vision.
It was 2008 and the 25-year-old lawyer from Peterborough, Ont., who was diagnosed with an incurable genetic eye disease that causes blindness in childhood, was recovering from an eye surgery in Florida as part of the clinical trial.
Three days after the surgery, Turner removed his eye patch and realized his vision had been partially restored.
“When I peeled back the patch, I was outside of the University of Florida on a nice bright, sunny day and I had never seen the sky like I had seen it before. It was just one of those things that the proof was right in the sight,” Turner told CTV’s Canada AM on Tuesday.
Turner was diagnosed with a disease called Leber’s congenital amaurosis when he was six years old. The eye disease is hereditary and affects around one in 80,000 newborns and is one of the most common causes of childhood blindness.
Turner’s family was told by doctors that the disease would lead to total blindness by the time he was 10.
But in 2007 scientists announced they had discovered the gene mutation that was responsible for causing the blindness.
The gene is called the NMNAT1 and doctors estimate it causes around five per cent of cases of Leber’s congenital amaurosis.
Turner was asked to participate in an experimental clinical trial that would treat his eye with gene therapy.
“When they contacted me in 2007 it was a huge breakthrough and represents so much hope because my fate along with any others who suffer from blindness and genetic blindness is that you will eventually lose all your sight. So this was a huge turnaround,” he said.
Doctors treated Turner by injecting a non-mutated version of the gene, as well as a non-infectious virus into his right eye. The virus spread the non-mutated gene and wherever it touched his eye, it restored his vision.
“It essentially made the gene of the eye work properly, as if it was always working,” he said.
Before the surgery Turner had around eight per cent vision, meaning he could see things in front of him and only in various shades of grey. He also relied on screen-reading software that converts text to audio to read.
Now Turner can see different colours and read on his own. He’s used his new skills to launch his own law practice in Oshawa, Ont.
Turner, who only had four per cent of his right eye treated hopes that some day he will be able to have more of his eye treated.
“My doctor down at the University of Pennsylvania, we always joke that I’ll be on the road driving one day—of course safely,” he said.
“We just have to keep in mind that for incurable and untreatable things, we have to keep hope, because science is moving along so quickly and it’s just such a positive and amazing thing.”