A group of international scientists believe they may have discovered a reason for one of the causes of blindness. If right, they hope a cure is not far away.

One of the major causes of blindness is age related macular degeneration. This accounts for around 50,000 cases in the United Kingdom alone each year. It is currently incurable.

However, that could be about to change. Scientists have discovered an enzyme called DICER 1 which they believe is primarily the reason behind the disability. In short – it stops working.

Researchers found that the enzyme was less active in people who possess the dry form of macular degeneration. When they turned off the gene which creates the enzyme in mice, they found the mice’s retina cells were damaged.

While extrapolation onto humans is a long shot it is great news nevertheless. As such, it is a possible breakthrough.

The macula is found in the middle of the retina. It is responsible for all the fine visual detail at the centre of our visual field. Unfortunately, as people get older this begins to break down which makes reading, driving and even recognising people difficult.

The disease affects around one in fifty people over the age of 50; it also affects one in five people over 85.

Speaking with the BBC, Professor Jayakrishna Ambati, from the University of Kentucky said: “This work opens many new doors of research.”

He added: “First, we need to identify various classes of molecules that can either increase DICER1 levels or block Alu RNA so that these can be evaluated in clinical trials.

“Second, we need to understand more about the biological processes that lead to reduction in DICER1 levels and the precise source of the Alu RNA transcripts.”

Echoing his comments, Professor Ian Grierson, who works at the school of clinical sciences at the University of Liverpool, said: “This is a great piece of science which provides another jigsaw piece which we need to put together with other findings.

“It was done in an animal model which is a long way from the patient; the breakthrough is we’ve got another player.”