Blindness: how better diagnosis of a rare illness might protect children’s sight

Children born with a rare illness called brittle cornea syndrome have fragile eyes, meaning common accidents such as being poked in the eye or hit by a ball can rupture their eyeball and leave them blind. Professor Graeme Black of the University of Manchester is researching the genetic causes of this rare illness in the hope of improving diagnosis. Early diagnosis could save children’s sight by alerting them to the need to wear special glasses that protect their eyes.

What is the problem and who does it affect?

“Brittle cornea syndrome, or BCS, is a rare and potentially devastating inherited disorder that can affect children in several ways,” explains Professor Graeme Black. “Children with the disorder often suffer some hearing loss, because they have floppy ear drums. They can also have loose joints, sometimes suffering dislocated hips. The biggest problem though is that the children have unusually thin corneas, which puts them at risk of severe vision problems and even blindness.”

The cornea is the clear window of tissue at the front of the eye that helps to protect our eyes and to focus light so that we can see. Children with BCS have fragile corneas, meaning common accidents can prove devastating. The children’s eyes can rupture if they are accidentally poked in the eye, for example, or if they are hit by a ball or a toy that is thrown across the room.

“If a child’s eye ruptures, their vision is normally badly affected and they often lose the eye altogether,” explains Professor Black “Subsequent vision problems, especially if combined with deafness, can have a profound impact on children’s lives.”

What is the project trying to achieve?

Frequently, BCS is not diagnosed until after a child’s eye has been ruptured and they have lost their sight in that eye. Earlier diagnosis could be hugely beneficial by providing an early warning signal – alerting children (and their families) to the fact that their eyes are much more vulnerable than normal to damage in everyday life. Children could then wear special protective glasses, and make changes to their lifestyle, which could stop them from going blind.

“We are investigating the genetics of BCS,” explains Professor Black. “Two genes have already been linked to the disorder. We are examining those genes in 25 people with BCS and 150 people with a more common, related disorder called keratoconus. We are also searching for other genes for BCS and investigating how genetic changes actually cause thinning of the cornea.”

This work could lead to new genetic tests that facilitate earlier diagnosis of BCS.

What are the researchers’ credentials? 

Professor Black has an outstanding international reputation for work on the genetics of inherited eye diseases. His team strives to turn research findings into real benefits for patients and has access to world-class facilities at its Manchester base, which includes the second-largest eye hospital in the UK.