British surgeons have claimed a world first after carrying out a gene therapy operation to tackle the most common cause of sight loss in the developed world.
Age-related macular degeneration (AMD) causes the deterioration of cells in the macular, the central part of the retina, and affects more than 600,000 people in the UK.
Medics at the John Radcliffe Hospital said their pioneering operation could have a real impact on the quality of life and independence of those who suffer from AMD.
The operation involves detaching the retina and injecting a solution containing a virus underneath.
Robert MacLaren, professor of ophthalmology at the University of Oxford, who carried out the procedure, said: "AMD is the number one cause of untreatable blindness in the developed world.
"A genetic treatment administered early on to preserve the vision in patients who would otherwise lose their sight would be a tremendous breakthrough and certainly something I hope to see in the near future.
"We're harnessing the power of the virus, a naturally occurring organism, to deliver the DNA into the patient's cells.
"When the virus opens up inside the retinal cell it releases the DNA of the gene we have cloned, and the cell starts making a protein that we think can modify the disease, correcting the imbalance of the inflammation caused by the complement system.
"The idea of this gene therapy is to 'deactivate' the complement system, but at a very specific point at the back of the eye, so the patient would otherwise be unaffected by it, and we hope that in future it will slow down the progression of macular degeneration."
The therapy is intended to preserve what vision patients have remaining and halt the effects of AMD.
It is hoped the procedure can be used early enough before the deterioration of eyesight begins.
