Seeing problems in genes can prevent sight loss

Genetic factors play a role in many eye diseases, including age-related macular degeneration (AMD) and glaucoma, the main causes of irreversible blindness.

Informing your optometrist of any family history of eye disease means relatives can be monitored and eye conditions diagnosed sooner, with earlier treatment to prevent sight deterioration.

Dr Dolores Conroy, director of research at eye charity Fight for Sight, says: “With a family history of glaucoma, there is a six to ten-fold increased risk. Glaucoma is easily detected in a routine eye check, with treatment given to preserve remaining sight.

“Recent research has identified non-modifiable genetic susceptibility for AMD, along with modifiable lifestyle risk factors, such as smoking and diet. Wet AMD can be treated if detected early.”

Dr Conroy says hyperopia – long-sightedness – and myopia – short-sightedness – are thought to result from interaction of genes and environmental factors. “In Asian populations, over two-thirds of school-leavers are myopic, probably due to spending long periods studying closely and not enough time outdoors,” she says.

Clinical trials are underway to replace defective genes for some inherited retinal disorders

Childhood eye conditions, such as lazy eye – amblyopia – and squint – strabismus – are often associated with family history, so the earlier detected, the better the likely treatment outcome.

Boots Opticians optometrist Carolyn Norman says: “Those above 40 with glaucoma family history can have free annual eye tests, because risk increases with age.”

Clinical trials are underway to replace defective genes for some inherited retinal disorders, caused by gene mutations passed down in families, for which there are no effective treatments.

AMD Alliance International (AMDAI) chief executive Narinder Sharma stresses the importance of updating your optometrist. He says: “AMD damage can be minimised, or even prevented, through sharing family history with the optometrist. If you have AMD in the family, get annual eye checks and take steps to lessen risks, for example, not smoking.

The Age-Related Eye Disease Study (AREDS) found eating greens and brightly coloured fruit and vegetables, plus oily fish, might delay onset.”

Mr Sharma says eye injections could slow wet AMD progression and sometimes even restore some vision.

AMDAI is hosting International AMD Week, from September 22 to 30, to launch its two-year global AMD awareness and prevention campaign.

Consultant ophthalmologist Nick Astbury says sunglasses for AMD sufferers are a sensible precaution. “More bright light on an already-stressed, light-sensitive organ may make matters worse,” he says, adding that people with advanced AMD in one eye may benefit from nutritional supplements.

Mr Astbury says research into gene therapy is vital to reduce inherited childhood blindness. “Some childhood eye conditions, such as retinopathy of prematurity and cataract, can be recognised early and effectively treated,” he says.

AMD causes central vision distortion, so some sufferers cannot read, cook or drive. Dr Susan Blakeney, of the College of Optometrists, points out that people don’t always notice if only one eye is affected. She advises: “Be aware of individual vision in each eye. Hold a hand over each eye in turn. If vision in one eye appears distorted, see an optometrist immediately.

“Through greater awareness about AMD and glaucoma, we hope to increase detection and encourage people to access support services.”