科學研究:10年後有望點眼藥防近視

　　A gene that causes shortsightedness has been pinpointed 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 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. 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 mportant risk factor for being short-sighted is having parents who are shortsighted and for the first time we are identifying genes 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, we have not previously understood how people become short-sighted. "

"We hope that by understanding the mechanisms 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."

英國科學家日前找到了誘發近視的基因，從而爲眼藥水改寫眼鏡歷史肅清了道路。十年之內，一種預防近視或讓近視不會再加深的藥物將會問世，並且被廣爲使用。

　　倫敦大學國王學院專家們所領導的一個國際小組的最新研究爲百萬人帶來了希望。

爲了找出這種與近視有關的首個基因，研究人員比較過4000多對英國雙胞胎的基因。因爲以雙胞胎來做研究比較，更容易區分出天與後天的不同影響。然後，他們又研究了1萬3000名英國人、荷蘭人和澳洲人的基因，印驗證了他們先前的研究結果。

倫敦大學國王學院的研究員、該研究的主要作者皮若-海斯說：“很多年來我們都知道近視的最重要風險因素是父母近視，如今我們首次發現這種缺損性遺傳的基因基礎。”

同樣來自倫敦大學國王學院的克里斯-哈蒙德說道：“近視是最常見的眼病，超過三分之一的英國人都是近視。近視程度嚴重的人羣將來有可能會失明。視網膜會像牆紙一樣從眼球后部開始脫落。”

“我們一直認爲環境因素，比如工作過度、缺少室外活動，是導致近視的原因，但此前我們一直不知道人們的眼睛是怎麼近視的。”

“我們希望藉助對相關機制的理解，預防孩子出現近視症狀，或是避免孩子度數加深。”

另外一項由荷蘭研究人員進行的研究確認了另外一個近視相關基因。最終，與近視相關的基因可能會有幾十個。

哈蒙德說，抵消近視基因作用、防止眼球過度生長的藥物10年內即可問世， 屆時其他療法也會出現，包括基因療法——給眼睛注入“健康”基因。

儘管眼藥水對已經近視的成年人沒有幫助，但對他們的孩子還是大有益處的。

然而，如今的年輕人很容易就可避免近視或降低度數，杜克大學的特里-揚說：“人們得到外面走走，看看地平線。如今很多工作讓眼睛持續緊張地盯着報紙和屏幕看。”