Gene therapy of choroideremia

Gene therapy has helped the British in the treatment of blindness

Copper news

Clinical trials of gene therapy for choroideremia, a hereditary disease that leads to blindness, have successfully begun in the UK. The first phase of clinical trials will involve 12 people; three of them have already been operated on, reports the Daily Mail (Injecting a virus into my eye saved my sight).

Choroideremia is a hereditary disease caused by the absence of one gene in the X chromosome. The development of the disease leads to degeneration of the choroid (vascular membrane of the eye), the pigment epithelium of the retina and, as a consequence, to blindness. Only men are susceptible to the disease, since they have only one X chromosome. The disease develops very slowly – blindness overtakes most patients by the age of 40-60. There is currently no treatment for choroideremia.

Images of the fundus of a healthy person and a patient with choroideremia
Photo: Charlotte Poloschek, MD, University Eye Clinic Freiburg, Germany – VM

The world's first treatment for choroideremia was developed by Professor Robert Maclaren together with his colleagues from Oxford and Professor Miguel Seabra from Imperial College London. Researchers have created a genetically modified version of the virus that delivers missing genetic material to retinal photoreceptor cells. Three to four weeks after the operation, the gene embedded in the DNA of the cells "turns on" and becomes active.

The first three patients who received gene therapy were operated under general anesthesia to deliver billions of viral particles to the retina with the help of the thinnest needle. Since the safety of such treatment will be proven only after the completion of this phase of clinical trials, each sufferer from choroideremia had only one eye operated on. One of the patients, 36–year-old Nick Tuftnell, noted a significant improvement in vision a year after the operation and plans to cure the second eye in the future.

Portal "Eternal youth" http://vechnayamolodost.ru19.03.2013