Mysteries of myopia may soon become clear

Huge pool of genetic data could hold answer to what causes short-sightedness and why it affects 80pc of Asians and 30pc of Westerners

PUBLISHED : Monday, 03 June, 2013, 12:00am
UPDATED : Monday, 03 June, 2013, 6:22am

Two professors are hoping to discover why Asians are nearly three times more likely to be short-sighted than Westerners.

They are taking part in a global study which has revealed that both groups share similar myopic-related genes. And they say the data will lead towards the development of genetic tests for short-sightedness, clinically known as myopia.

It is estimated that up to 80 per cent of Asians are myopic, compared with just 30 per cent of Western populations.

"The genes are giving us an insight into how myopia is developed," said Dr Jeremy Guggenheim, an associate professor at Polytechnic University's school of optometry.

Many previous studies have revealed the link between environmental factors and short-sightedness, but research into its genetic causes is just beginning.

The latest study saw 64 universities and research institutes in 13 countries collect data from more than 37,000 people of European ancestry and 8,300 of Asian ancestry. Some 600,000 DNA markers in each person were looked at.

So far, 24 genes that increase the risk of myopia up to 10 times have been identified. Of those, 16 have been found in Western people, and eight have also been found in Asians. Initial research suggests the remaining genes may be shared between the two populations, too.

Guggenheim said the results were not what he was expecting because so many more Asians were short-sighted.

He said there were many more genes related to myopia to be uncovered. Further studies could also be done to find out whether there were any interactions between genetic and environmental factors, such as time spent outdoors and reading.

Professor Yip Shea-ping, associate head of the university's health technology and informatics department, who is working with Guggenheim, said people may think short-sightedness was no big deal, but those with a high level of myopia also have a high chance of developing eye conditions in old age, such as cataracts and retinal detachment.

He said genetic tests would enable early intervention - such as the possibility of wearing special contact lenses to slow down the onset of myopia.