Researchers from the Universities of Cardiff and Bristol have devised a test that could in future help to identify children at risk of developing a very common eye condition.
Short-sightedness, or myopia, usually develops during childhood and is thought to affect up to one in three people in the UK.
The condition - which is increasing in prevalence worldwide - occurs when the eye grows too long, meaning light does not focus on the light-sensitive retina, causing distant objects to appear blurred.
Researchers say Myopia is easily detected with an eye test and corrected with use of glasses or contact lenses but it increases the risk of eye disorders, like glaucoma and cataracts.
Current treatments cannot halt its onset but can slow progression, meaning a genetic test could be key to early intervention.