An exciting advance has been made by scientists in the USA and Britain in treating eye disease using gene therapy. Clinical trials on males born with choroideremia, a degenerative eye condition, affecting about one in fifty thousand that leads to blindness in middle age, has been under way with encouraging results.
Hope to Inherited Retinal Disease Sufferers
Choroideremia is a gene related disease primarily affecting males who are born with a deficient gene in the X chromosome.
Often by the early teens, the retinal cells at the back of their eyes begin to degenerate with a gradual ‘tunnelling’ of the vision and an increasing problem with night and dim light vision.
This new gene therapy, still in in the early stages of development, gives hope to those born with inherited retinal diseases whose sight will be lost, often at an early age.
Oxford University Leads The Way
The procedure, carried out at Oxford University, is to inject into the eye a harmless virus carrying the defective gene which will make its way through the vitreous fluid and infect retinal light sensing cells with the defective gene.
To date treatment has only been given to patients with advanced stages of the disease but results have shown that the failure of the light sensitive cells has been halted and that there are indications of an improvement in sight.
As the surgery started with the first patient near the end of 2011 with the last of the patients operated on six months ago, researchers are suggesting that it is still too early to conclude whether the treatment will continue stopping the loss of light sensing retinal cells but the early indications are positive.
The Earlier The Treatment, The Better The Result
The surgery takes up two hours to perform, similar to the time taken for cataract lens replacement and some patients in the trial are reporting a improvement in their vision quite soon after the procedure.
It has been emphasized by the consultant surgeon, Robert MacLaren, that the earlier the procedure is carried out before the vision has deteriorated to any great extent, the better will be the chances of keeping the disease at bay. Poor night vision is an early indication of the disease.
Hope Held Out For Eventual Success with Age Related Macular Degeneration
The science of gene therapy and the use of a benign virus to reach and restore light sensing retinal cells holds out tremendous hope for the successful treatment of the other previously untreatable eye diseases that lead to blindness.
Macular degeneration eye disease which many of both sexes suffer from in advancing middle age could be halted and reversed if this gene therapy treatment proves successful in ongoing clinical trials. Mr Robert MacClaren reckons that if all continues to go well, the treatment will be available to all within five years.
This gene therapy will be a massive step forward in curing blindness, whatever the cause.