A UK doctor has transferred embryonic stem cells to cure blindness in a patient suffering from age-related macular degeneration.

A doctor in the UK has performed the world's first embryonic stem cell operation using a "patch" technique in the hope of finding a cure for blindness in some patients.

Professor Lyndon Da Cruz from Moorfields Eye Hospital in London carried out the operation last month on a woman with age-related macular degeneration (AMD).

The procedure involves taking a single stem cell from an embryo and growing it into a "patch" or sheet of cells that can be transplanted into the eye.

Experts hope to be able to reverse vision loss in people with AMD, which affects more than 600,000 people in the UK and is the leading cause of blindness in adults.

The woman does not wish to be named. She has had no complications to date.

A study on 10 patients with a form of the disease known as wet AMD has been launched, with the hope of extending the findings to people with the more common dry AMD.

AMD affects one specific area of cells that are either damaged or completely missing.

In the new technique, a stem cell from an embryo is grown in the lab to create a single layer of retinal pigment epithelium cells.

These cells form a thin sheet that lines the inside of the eye, under the retina. A healthy layer is critical to normal sight.

When these cells are damaged or lost, they are thought to lead to AMD.

Prof Da Cruz said embryos were the "perfect source" of cells, adding: "The reason we are very excited is that we have been able to create these very specific cells and we have been able to transfer them to the patient.

The cells were taken from donated embryos, created during IVF treatment but never used.

Prof Da Cruz has started the trial with wet AMD patients because there is potential to restore sight faster in these cases, following sudden vision loss.

"We would hope within the first three months to get some idea of whether it is working," he said.

The operation is a major milestone in the London Project to Cure Blindness, which is a partnership between Moorfields, the University College London Institute of Ophthalmology and Britain's National Institute for Health Research.

Pharmaceutical giant Pfizer joined the partnership in 2009 with the goal of creating a potential therapy for AMD.