三级aa视频在线观看-三级国产-三级国产精品一区二区-三级国产三级在线-三级国产在线

US EUROPE AFRICA ASIA 中文
World / Reporter's Journal

Blue eyes or brown? Blonde or brunette? The age of easy gene-editing is here

By CHRIS DAVIS (China Daily USA) Updated: 2015-11-25 06:35

Animal breeding is nothing new. And it has paid off. What a stale and dull place the world would be without St. Bernards, Belgian draft horses, Persian cats, all the domesticated critters selectively bred and crossbred for their valued traits, be it speed, color, strength or demeanor. The registry of thoroughbred horses alone makes the House of Windsor's family tree look like a mere mulberry bush. And the American Kennel Club's 160-plus breeds of dogs are stunning proof of the vast pallet of color, shape and size DNA offers.

Blue eyes or brown? Blonde or brunette? The age of easy gene-editing is here

All of that kind of breeding, of course, was done the old-fashioned way. Selecting the right pairs, checking their lineage to avoid inbreeds, rolling the dice and waiting out Mother Nature's timetable to see if the match-ups produced the desired results — like transforming a bloodhound into a Golden retriever.

Well, apparently those days are past. Scientists have a new tool that not only speeds the whole process up, but also lets them target the desired result with pinpoint accuracy. It's called CRISPR and its place of birth is presently a point of contention between scientists at MIT and Cal-Berkeley. But a few things about it are clear: it's cheap, easy to use, getting easier and more efficient all the time, and the Chinese scientific community is very into it.

CRISPR is one genie that is not going back into its bottle any time soon.

CRISPR (it stands for "clustered regularly interspaced short palindromic repeats", whatever that means) basically uses enzymes to, what we call in publishing, "line edit" strands of DNA, a task that, as Darwin suggested, the randomness of Nature has been doing since life began.

Now, with a genome road map and CRISPR, anything goes, and it's going fast, so fast that there doesn't seem to be enough time to think through all of the ethical implications, much less the risks. Genetically "edited" organisms could wreak havoc in the ecosystems they evolved with, for one thing.

As Stanford biologist Stanley Qi told the journal Nature: "This power is so easily accessible by labs — you don't need a very expensive piece of equipment and people don't need to get years of training to do this. We should think carefully about how we are going to use that power."

The current issue of Scientific American reports how CRISP is being used in western China at the Shaanxi Provincial Engineering and Technology Research Center for Shaanbei Cashmere Goats, which yield what is considered the world's best cashmere. Scientists there have used CRISPR to create "a new kind of goat, with bigger muscles and longer hair than normal."

Scientists basically went into goat embryos and "deleted" the two genes that hold back muscle and hair growth. The pay off was 10 kids with bigger muscles and longer hair and "no other abnormalities," the report said. To geneticist Lei Qu, it's just "a simple way to boost the sale of goat meat and cashmere sweaters from Shaanxi."

The number of scientific papers worldwide describing uses of CRISPR are outstripping those using other techniques, and China is part of the trend. CRISPR-tweaked sheep, pigs, monkeys and dogs are described in what SA describes as a "flurry of papers by Chinese scientists."

It's use is a "priority" with the Chinese Academy of Science, according to Minhua Hu, a geneticist at the Guangzhou General Pharmaceutical Research Institute who was part of a team that produced Hercules, an unusually muscled beagle who lives up to his name.

Beefing up meat on the hoof to feed a growing appetite for protein is well within the ethical realm of animal husbandry. But the big elephant in the room remains — where do you stop? And that line seemed to be crossed last April when Chinese scientists announced that they had used CRISPR to modify human embryos — the first time in the world.

Granted they were nonviable embryos, obtained with the consent of a fertility clinic, and their aim was to edit out a gene that leads to beta-thalassemia, a deadly genetic blood disorder.

But the work caused an uproar and the warnings issued then still ring true today, even more so perhaps.

Harvard biochemist and stem-cell expert George Q. Daley said the risks included unwanted or harmful defects. "It would be distressing to cause one disease while attempting to erase another," he told China Daily.

He also said that "genetic engineering will raise the most fundamental issues over how people are to view our humanity in the future, and whether we are going to take the dramatic step of taking control of our genetic destiny."

It already has.

Contact the writer at chrisdavis@chinadailyusa.com.

Trudeau visits Sina Weibo
May gets little gasp as EU extends deadline for sufficient progress in Brexit talks
Ethiopian FM urges strengthened Ethiopia-China ties
Yemen's ex-president Saleh, relatives killed by Houthis
Most Popular
Hot Topics

...
主站蜘蛛池模板: 亚洲成人在线视频播放 | 亚洲综合网在线观看首页 | 久久99精品一久久久久久 | 久久青青草原精品老司机 | 国产日本三级在线播放线观看 | 日本黄色大片视频 | 久久久美女 | 久久国产精品久久久 | 男人的天堂久久精品激情 | 好大水好多好爽好硬好深视频 | 亚洲女同视频 | 在线国产视频观看 | ww在线观视频免费观看 | 日韩永久免费视频 | 欧美黄色片 一级片 | 伊人久久综合视频 | 亚洲www网站 | 日韩爽爽视频爽爽 | 亚洲欧美另类在线观看 | 国产视频久 | 中文字幕一区二区三区精彩视频 | 成人午夜做爰视频免费看 | 午夜亚洲精品久久久久 | 国产精品青草久久久久婷婷 | 亚洲国产第一区二区香蕉日日 | 色永久 | 男女免费高清在线爱做视频 | 久久99中文字幕伊人 | 成人在色线视频在线观看免费大全 | 欧美在线看欧美高清视频免费 | 一级一片免费视频播放 | 在线精品日韩一区二区三区 | 成人超污免费网站在线看 | 国产高清一级毛片在线不卡 | 91视频苹果版 | 国内一级片 | 精品国产自在现线久久 | 国产成人精品免费视频网页大全 | 可以免费观看一级毛片黄a 可以免费观看欧美一级毛片 | 亚洲经典激情春色另类 | 日本一二区免费 |