From Scientific American 科學人又來了！蝦米?西藏人才是真正的X-Men?!

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我超喜歡X戰警這系列的影片，每次都會問自已，如果我也可以是個Mutant，我想要選擇哪種超能力呢？根據下面這篇科學人雜誌報導：原來西藏人就是某種X-Men咧，因為有九成的西藏人體內有著足以適應高山生活的變種基因。這對我們這些平地人來說，這還真能算是某種超能力呢！

NPR與Scientific Americans都是英文聽力最佳的課外補品，大家要反覆聽，多聽，消化生字，一段時間之後，自然看得到成果。

Most Tibetans Genetically Adapted to the High Life

Ninety percent of Tibetans share a genetic mutation that prevents their blood from becoming dangerously clogged with red blood cells at high altitudes—a response that can be deadly for non-native mountaineers. Karen Hopkin reports.

When you hear the word “mutation變種,” you may think of something destructive, or of Marvel’s X-Men. But some mutations—which are just differences in DNA—can be historic. Take, for example, a genetic sequence 基因序列found in the vast majority極大多數 of people from Tibet.西藏人

Millions of Tibetans spend their days at average elevations of nearly 15,000 feet—that’s more than half the height of Mount Everest世界第一高峰聖母峰. Up there, the air is thin—with 40 percent less oxygen than at sea level海平面. That lack of O2 would leave most Westerners struggling for breath, but Tibetans seem to breathe easy.

To find out how these highlanders cope, researchers compared the DNA of 90 Tibetans to that of people who are not altitude adapted無法適應高海拔的稀薄空氣. And they discovered a single change that prevents Tibetans’ blood from becoming dangerously clogged with red blood cells高山症(紅血球與血紅素增多問題)—a response that can be deadly for non-native mountaineers. The finding is described in the journal Nature Genetics自然遺傳學期刊.

This mutation appears to have originated just 8,000 years ago. But it’s so advantageous具有優勢的 that today nearly 90 percent of Tibetans have it. While it’s virtually absent in even closely related lowland neighbors.

The finding demonstrates that a really useful mutation will always rise to the top.往上升(浮到上面去)這種說法一語雙關，因為西藏人住在高山上，所以也有「基因變種好適應高山生活所需」之意。