A team of surgeons in Oxford have used a pioneering new form of gene therapy to stop six of their patients going blind–and it’s hoped the technique could be used to treat blindness more generally.
The patients all suffer from a genetic condition known as choroideremia, which causes the light-detecting cells at the back of the eye to slowly die. Patients with the condition initially struggle to see in low-light conditions, but their sight gradually declines until most sufferers lose their eyesight completely by the time they reach middle age. Worst of all, there’s no treatment.
Prof Robert MacLaren and his team, however, have been experimenting with a new technique which sees them inject functioning copies of the CHM gene — known to be faulty in these patients — directly into the retina. According to results published today in The Lancet, the technique clearly works: it’s stopped six patients going blind.
The researchers report that two patients not only saw their eyesight stabilise, but actually improve — experiencing huge improvements in their ability to see at night, as well as being able to read three lines further down an optician’s sight chart. “My colour vision improved. Trees and flowers seemed much more vivid and I was able to see stars for the first time since I was 17 when my vision began to deteriorate,” one of the patients told the BBC.
That’s wonderful news, but it could get even better too. Speaking to the BBC, Prof MacLaren explained that “[t]he mechanisms of choroideremia and what we are trying to do with the treatment would broadly be applicable to more common causes of blindness.” In other words, the gene therapy could one day be used to treat many forms of blindness, not just this one.We can’t wait to see if that turns out to be the case. [The Lancet via BBC]