研究:10年后有望用眼药防近视

    A gene 1 that causes shortsightedness has been pinpointed 2 by British scientists, paving the way for eye drops that could make glasses history. Within just ten years, a drug that prevents short-sightedness or stops it in its tracks could be in widespread use。

    The latest research, by an international team led by experts at King's College London (KCL)， offers hope to millions。

    To find the gene, the first to be linked to short-sightedness, or myopia, the researchers compared the DNA 3 of more than 4,000 British twins. Twins are often used in such studies because it is easier to distinguish the different effects of nature and nurture 4. They then confirmed their results by studying the genetics of another 13,000 British, Dutch and Australian individuals。

    KCL researcher Pirro Hysi, the study's lead author, said: "We have known for many years that the most important risk factor for being short-sighted is having parents who are shortsighted and for the first time we are identifying genes 5 that may be involved in passing on this susceptibility."Chris Hammond, also of KCL, said: "Myopia, or shortsightedness, is the most common eye problem, affecting over a third of adults in the UK. People who are extremely short-sighted carry significant risks of future vision loss. The retina can peel away from the back of the eye like wallpaper off a wall.""While we believe that environmental risk factors such as a lot of close work and lack of outdoor activity are implicated 6, we have not previously 7 understood how people become short-sighted. ""We hope that by understanding the mechanisms 8 we can stop children from becoming shortsighted and stop short-sighted children from becoming more short-sighted."A second study, by Dutch researchers, identified a second short- sightedness gene. Ultimately, there could be dozens behind the condition。

    Drugs that counter their effect and stop the eyeball from overgrowing could be available in just a decade, said Hammond. Other options include gene therapy - injecting "healthy" genes into the eye。

    Although the eye drops would not help adults who are already short-sighted, they could be of huge benefit to their children。

    However, today's youngsters can take some simple steps to try to discourage shortsightedness. Terri Young of Duke University said: "People need to go outside and look at the horizon. Today's near work forces our eyes to be constantly in tension to focus on reading papers and watching monitors."