A British teenager who suffered from a rare eye disorder which meant he was unable to see in the dark has had his eyesight partly restored by revolutionary new gene treatment, it was reported Monday.
Steven Howarth, 18, is one of three patients who took part in a medical trial carried out by scientists at London's renowned Moorfields Eye Hospital and University College London, the New England Journal of Medicine reported.
The experimental therapy involves inserting genes into the back of the patient's eye to correct a genetic fault that stops their retinas detecting light properly, a condition known as Leber's congenital amaurosis (LCA), dpa reported.
The two other patients, aged 17 and 23, suffered no ill-effects but did not report any improvement, the US science journal said.
"Now, my sight when it's getting dark or it's badly lit is definitely better. It's a small change but it makes a big difference to me," said Howarth, a student and guitarist.
"Before the operation, I used to rush home from college when it started to get dark because I was worried about getting around," Howarth, from Bolton, north-west Britain, said.
LCA is an inherited disorder that causes progressive deterioration in vision and can lead to blindness in teenagers. It occurs when faulty genes, called RPE65, stop the layer of cells at the back of the eye working.
"Showing for the first time that gene therapy can work in patients with eye disease is a very significant milestone," said Professor Robin Ali, whose team conducted the trial, which was backed by 1 million pounds (2 million dollars) from the British government.
"This trial establishes proof of principle of gene therapy for inherited retinal disease and paves the way for the development of gene therapy approaches for a broad range of eye disorders," he said.
Lynda Cantor, founder of the British Retinitis Pigmentosa Society, said: "Proving the principles behind gene therapy, and that it can be used safely in the retina, is fantastic news," she said.