October 28, 2011
Gene Therapy May Improve Some Forms Of Blindness
A UK man is being treated for the progressive genetic disorder, choroideraemia, in an attempt to reverse his blindness.
Jonathan Wyatt was able to see normally until about the age of 19 when he began having problems seeing in the dark. He was told by doctors that his vision would get progressively worse until eventually going blind, reports BBC News.Poor eyesight didn´t stop Wyatt, now 63 years old, from a career as a barrister but 10 years ago he found himself having difficulty reading statements in dimly-lit courts.
The progressive genetic disorder, choroideraemia, affects about 1,500 people in Britain, often leads to blindness by their 40s, Nick Collins of The Telegraph reports. The advanced gene therapy technique, performed by researchers from Oxford is the first attempt to correct the genetic defect in the cells lining the back of the eye.
Researchers injected ten billion copies of the missing gene REP 1, directly into his left eye, while leaving the right untreated as a “control”. Inserting copies of the gene into an empty virus particle, which was programmed to move towards cells in the eye called photoreceptors, scientists hope to activated the gene and prevent future damage.
Researchers expect to know if the treatment has worked within the next two years, and will treat Wyatt´s other eye if the results are positive.
Wyatt´s doctor, Robert MacLaren explained to BBC, “If this works with then we would want to go in and treat patients at a much earlier stage in childhood, effectively where they still have normal vision and can do normal things to prevent them from losing sight.”
“That is a genetic disease and I have no personal doubt in future that there will be a genetic treatment for it,” he says.
According to lead researcher Robin Ali, the trials have shown not only that gene therapy is safe - but that there has been significant improvement in some patients. “It is very exciting to see the start of another ocular gene therapy trial and the field moving so rapidly in recent years,” he told Pallab Ghosh of BBC.
“In the last 12 months, several new gene therapy trials for the treatment of various retinal disorders have been initiated and further trials are likely to start very soon. We are all looking forward to seeing the results.”
The concept of using gene therapy has been around for more than 20 years for various conditions but with, some notable exceptions, it´s an idea that´s failed to live up to its hype. Now, however, it seems that the technique is beginning to deliver, at least in treating sight disorders.
According to Sir John Bell, president of the Academy of Medical Sciences, these very early trails in Oxford, London and in the US suggest that a whole host of sight disorders could, be treatable “within the next 10 years.”
“Of all the things that are available for this particular set of diseases this is by far the most exciting,” he told BBC.
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