Find could cut risk of thousands going blind

SCIENTISTS investigating the most common form of adult blindness have made a breakthrough discovery, thanks to a UK-based collaboration.

Age-related macular degeneration usually hits those in their 50s and 60s and affects around 600,000 people in Britain alone.

There are two types of the condition –Wet and Dry – and no cures.

The only treatment for Dry AMD, is wearing specs, while Wet AMD can be slowed with light treatment or jabs.

But now a University of Manchesterled team has discovered the condition is caused by the failure of proteins which regulate the immune system.

Their early findings suggest that between 40 and 50 per cent of AMD sufferers have elevated levels of at least one of the five “FHR” proteins.

And they hope their discovery will not only help develop sight-saving pharmaceutical treatments, but could one day herald a test to identify those at risk from AMD.

Dr Richard Unwin, of The University of Manchester’s Stoller Biomarker Discovery Centre, said: “This is hugely important for people with AMD.

Measuring the levels of these FHR proteins has been a big challenge over the last few years.

“It is technically quite challenging because they are present at low levels in the blood and are very similar to each other.

“By using state-of-the-art mass spectrometry methods, we can now confidently measure these proteins.

“We can show for the first time what is an important, if not the most important, factor in how AMD develops.”

Hope

Dr Unwin added: “It’s important to stress studies over time need to be carried out before we can say with authority these proteins are able to predict risk.”

But he said a parallel study by Dutch scientists had arrived at similar conclusions about proteins and AMD.

The University of Manchester research, a collaboration between scientists in Manchester, London and Tubingen in Germany, was funded by the Medical Research Council and published this week in the American Journal of Human Genetics.

Scientists have long known that inflammation at the back of the eye plays a role in AMD development.

It is caused when part of the body’s innate immune system, called the complement pathway, becomes over-activated.

The pathway’s activity is regulated by genes, so scientists studied levels of the FHR proteins produced by these genes – and discovered they are higher in people who have AMD.

Now the team hopes intervening at an early stage could stop the progression of the disease.

Prof Simon Clark, at Eberhard Karls University of Tubingen, said: “This really marks a step-change in our understanding around the driving mechanisms behind AMD.

“All higher levels of at least one of the five FHR proteins are now known to be associated with AMD risk.

“Being able to measure these proteins in patients’ blood will be vital in identifying patients who will react to FHR-targeting therapies in the future.”