PBS高端访谈:关于CRISPR基因编辑技术在进化方面的讨论

 　　JUDY WOODRUFF: As Vice¹ President Biden said earlier, innovations in genetics could be crucial to finding cures for diseases like cancer.

　　One of the most significant developments in this field is the newly discovered ability to modify the very genes⁴ in our DNA⁵. The technique is known by the acronym⁶ CRISPR.

　　William Brangham has our conversation.

　　WILLIAM BRANGHAM: CRISPR is a technique that allows scientists to go into the DNA of a plant or an animal or even a human being and remove or replace a small part of that organism's genetic³ code.

　　This technique, which can be used to improve crops, eliminate genetic diseases, or specifically target the viruses and pathogens that have killed billion, could be a revolutionary advancement⁷.

　　The potential for CRISPR is described in the recent issue of The New Yorker. The story is called "Rewriting the Code of Life."

　　And I'm joined now by its author, New Yorker staff writer Michael Specter. He joins me from California.

　　Michael Specter, welcome.

　　In your story, you profile a young scientist named Kevin Esvelt. And I want to quote a line from your story. You say that Esvelt directs the — quote — "sculpting⁸ evolution group at MIT, where he and his colleagues are attempting to design molecular⁹ tools capable of fundamentally altering the natural world."

　　I mean, that's a pretty extraordinary set of ambitions. What are they trying to do?

　　MICHAEL SPECTER, The New Yorker: You know, they're trying to look out the problems we have in health, in crops in a variety of ways, and rewrite DNA, which is the basic code of life, so that it can make us healthier, safer, protect crops, protect trees, protect endangered species.

　　It's a tremendously energetic and ambitious idea. And it has — like all wonderfully ambitious ideas, it has great risks, too.

　　WILLIAM BRANGHAM: You report on a particular experiment they're running up in Nantucket trying to target Lyme disease.

　　Can you explain what they're hoping to do there?

　　MICHAEL SPECTER: Mostly, people think about Lyme disease in deer. And there is a relationship.

　　But the real reservoir for Lyme is the white-footed mouse. At Kevin Esvelt at MIT said, gee¹⁰, let's rewrite the DNA of the mouse so that it is resistant¹¹ to the Lyme tick, so when a Lyme tick bites it, it doesn't matter.

　　And when you do that, you sort of break this chain of transmission between mice and deer and humans. And if you did that enough, and if you really rewrote the DNA — mice are not that rapid, but they're relatively¹² rapid at reproducing — and you can quite easily see a way in which you would get rid of that disease.

　　关于CRISPR基因编辑技术在进化方面的讨论

　　WILLIAM BRANGHAM: I mean, as you describe it in this piece, CRISPR is really putting us in the driver's seat for evolution, and not only to control, in some ways, evolution, but to accelerate evolution.

　　Am I understanding that this just seems to be a tremendously — tremendous potential for this?

　　MICHAEL SPECTER: I think the particularly revolutionary thing here is the combination of CRISPR, which is an editing program — it's like editing something on your computer so that you can cut and paste words — combining that with this phenomenon called gene² drive.

　　WILLIAM BRANGHAM: Gene drive? And gene drive…

　　MICHAEL SPECTER: Yes.

　　Gene drive is something that scientists have known about for a long time. We all are supposed to get one copy of a gene from each of our parents. And that's usually what happens. That's Mendelian genetics.

　　But every once in a while, there's something called a selfless gene. A gene figures out a way to be tricky¹³, to be counterfeit¹⁴, to cram¹⁵ itself in where it ought not be.

　　And a guy named Austin Burt, who teaches at Imperial College in London, figured this out sometime ago. And he basically said, gee, if we could use those selfish elements the way we wanted, we could interrupt some things. We could make malarial¹⁷ mosquitoes unable to carry malaria¹⁶.

　　And he named a bunch of things like that. But it was theoretical then, because they didn't have this fantastic tool. Now you have the tool and you have this phenomenon. And when you put them together, you can really envision doing this. And, in fact, it's being done in labs.

　　WILLIAM BRANGHAM: As you write in the piece, you say that CRISPR could enormously improve the world, but it could also endanger the world.

　　How could gene editing endanger the world?

　　MICHAEL SPECTER: Well, I am not an alarmist, but if you can reedit the genes of a mosquito so that it can't carry malaria, you can also reedit the genes of a mosquito so that it carries something really bad and…

　　WILLIAM BRANGHAM: Use it as a weapon?

　　MICHAEL SPECTER: Sure.

　　You don't have to be a science fiction writer anymore to believe that it would be possible to engineer a species — and the mosquito, our deadliest foe¹⁸, is an excellent example — to transmit something bad.

　　We're very focused on being able to break the transmission of this terrible thing, malaria, and also Zika and dengue and many other things, but the truth is, that could happen.

　　And another thing that could happen is mistakes get made. When you're talking about editing DNA, you're talking about changing a species. And that's not a minor¹⁹ thing. That's a fundamental, powerful choice. And it will require some tremendous forethought.

　　WILLIAM BRANGHAM: So, how are researchers, policy-makers talking about this, thinking about this? How do they propose that we manage this awesome²⁰ technology?

　　MICHAEL SPECTER: Well, I actually think researchers are doing a fairly good job of trying to think this out.

　　And what that mostly means is, they're working in the labs, but they're very aggressively reaching out to communities. I don't think policy-makers so far have a clue. I mean, they don't know what's coming. They're so far behind in regulation, it's even difficult to understand how you would even talk about regulating this technology.

　　But with the malaria, Austin Burt, who I mentioned, runs something called Target Malaria. And he and a large group of people are working on editing enough of these mosquitoes so that they wouldn't be able to transmit malaria.

　　And he's in Africa already, years before he would ever send a mosquito there, talking to people, teaching people on the ground what the choices are, so they themselves can make this choice.

　　This isn't a case where a bunch of Western scientists are going to fly in somewhere with 400 million mosquitoes and release them and say, congratulations.

　　But there is the possibility of getting people to understand this and make their own decisions. And if it worked, getting rid of malaria is a big deal, and it would also actually be cheap, because there's no vaccines²¹, there's no drugs, there's no coming back.

　　We're not there yet, but it's certainly possible.

　　WILLIAM BRANGHAM: All right, the article is "Rewriting the Code of Life."

　　Michael Specter, thank you so much.

　　MICHAEL SPECTER: My pleasure.

1 vice   

n.坏事；恶习；[pl.]台钳，老虎钳；adj.副的

参考例句：

• He guarded himself against vice.他避免染上坏习惯。
• They are sunk in the depth of vice.他们堕入了罪恶的深渊。

2 gene   

n.遗传因子，基因

参考例句：

• A single gene may have many effects.单一基因可能具有很多种效应。
• The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。

3 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

4 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

5 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

6 acronym   

n.首字母简略词，简称

参考例句：

• That's a mouthful of an acronym for a very simple technology.对于一项非常简单的技术来说，这是一个很绕口的缩写词。
• TSDF is an acronym for Treatment, Storage and Disposal Facilities.TSDF是处理，储存和处置设施的一个缩写。

7 advancement   

n.前进，促进，提升

参考例句：

• His new contribution to the advancement of physiology was well appreciated.他对生理学发展的新贡献获得高度赞赏。
• The aim of a university should be the advancement of learning.大学的目标应是促进学术。

8 sculpting   

雕刻( sculpt的现在分词 )； 雕塑； 做（头发）； 梳（发式）

参考例句：

• The quality of the result is determined by a Craft( sculpting) check. 由手艺（刻）定决定结果质量如何。
• Another difficulty in the process of ice sculpting is time control. 冰雕过程中的另一项困难是时间的掌控。

9 molecular   

adj.分子的；克分子的

参考例句：

• The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。
• For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时，分子的碰撞就停止了。

10 gee   

n.马；int.向右！前进！，惊讶时所发声音；v.向右转

参考例句：

• Their success last week will gee the team up.上星期的胜利将激励这支队伍继续前进。
• Gee,We're going to make a lot of money.哇！我们会赚好多钱啦！

11 resistant   

adj.(to)抵抗的，有抵抗力的

参考例句：

• Many pests are resistant to the insecticide.许多害虫对这种杀虫剂有抵抗力。
• They imposed their government by force on the resistant population.他们以武力把自己的统治强加在持反抗态度的人民头上。

12 relatively   

adv.比较...地，相对地

参考例句：

• The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
• The operation was relatively painless.手术相对来说不痛。

13 tricky   

adj.狡猾的，奸诈的；(工作等)棘手的，微妙的

参考例句：

• I'm in a rather tricky position.Can you help me out?我的处境很棘手，你能帮我吗？
• He avoided this tricky question and talked in generalities.他回避了这个非常微妙的问题，只做了个笼统的表述。

14 counterfeit   

vt.伪造，仿造；adj.伪造的，假冒的

参考例句：

• It is a crime to counterfeit money.伪造货币是犯罪行为。
• The painting looked old but was a recent counterfeit.这幅画看上去年代久远，实际是最近的一幅赝品。

15 cram   

v.填塞，塞满，临时抱佛脚，为考试而学习

参考例句：

• There was such a cram in the church.教堂里拥挤得要命。
• The room's full,we can't cram any more people in.屋里满满的，再也挤不进去人了。

16 malaria   

n.疟疾

参考例句：

• He had frequent attacks of malaria.他常患疟疾。
• Malaria is a kind of serious malady.疟疾是一种严重的疾病。

17 malarial   

患疟疾的，毒气的

参考例句：

• Malarial poison had sallowed his skin. 疟疾病毒使他皮肤成灰黄色。
• Standing water like this gives malarial mosquitoes the perfect place to breed. 像这样的死水给了传染疟疾的蚊子绝佳的繁殖地点。

18 foe   

n.敌人，仇敌

参考例句：

• He knew that Karl could be an implacable foe.他明白卡尔可能会成为他的死敌。
• A friend is a friend;a foe is a foe;one must be clearly distinguished from the other.敌是敌，友是友，必须分清界限。

19 minor   

adj.较小(少)的，较次要的；n.辅修学科；vi.辅修

参考例句：

• The young actor was given a minor part in the new play.年轻的男演员在这出新戏里被分派担任一个小角色。
• I gave him a minor share of my wealth.我把小部分财产给了他。

20 awesome   

adj.令人惊叹的，难得吓人的，很好的

参考例句：

• The church in Ireland has always exercised an awesome power.爱尔兰的教堂一直掌握着令人敬畏的权力。
• That new white convertible is totally awesome.那辆新的白色折篷汽车简直棒极了.

21 vaccines   

疫苗，痘苗( vaccine的名词复数 )

参考例句：

• His team are at the forefront of scientific research into vaccines. 他的小组处于疫苗科研的最前沿。
• The vaccines were kept cool in refrigerators. 疫苗放在冰箱中冷藏。