美国国家公共电台 NPR As Made-To-Order DNA Gets Cheaper, Keeping It Out Of The Wrong Hands Gets Harder

 

DAVID GREENE, HOST:

DNA¹ encodes all of our genetic³ information. So you might find it surprising that it is getting easier to make DNA in a lab. In fact, some companies are cranking out huge amounts of cheap, made-to-order DNA. So what are the chances, though, that it could be misused⁵? NPR's Nell Greenfieldboyce takes a look.

NELL GREENFIELDBOYCE, BYLINE⁶: DNA is amazing. It's a kind of code made up of molecules⁷ known by their first letters - A, C, G and T. Strung together, these letters can form genes⁸, biological instructions that can get cells to do stuff, like make insulin or grow hair.

Patrick Boyle is showing me around a Boston biotech company called Gingko Bioworks.

PATRICK BOYLE: You know, I finished my Ph.D. in 2012, and over my - the course of my entire Ph.D., working with a few other people, we synthesized six genes.

GREENFIELDBOYCE: But, oh, how times have changed.

BOYLE: Today, we're synthesizing more than 10,000 genes every month.

GREENFIELDBOYCE: The workers here are like computer programmers, only the code they write is DNA code. Their designer DNA gets inserted into cells, like bacteria, yeast⁹, fungi¹⁰, to try to make them spew out chemicals that can be used as new drugs or food ingredients.

BOYLE: We're coming up with thousands of new designs on a computer, printing out the DNA for them, booting up that DNA, seeing what it does and then iterating on those designs.

GREENFIELDBOYCE: When he says printing out DNA, he means it literally¹¹.

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GREENFIELDBOYCE: The technology used for inkjet printing has been adapted to print short fragments of DNA onto glass slides. Those fragments then get assembled into larger and larger pieces in a highly automated¹² process.

BOYLE: So many of the robots that you see behind you are basically pipetting, you know, liquid around to put different fragments together to build the correct, full design.

GREENFIELDBOYCE: Over the last decade, the cost of making a pair of DNA letters - those A, C, T and Gs - has dropped from $1 to less than 10 cents.

BOYLE: We can actually, finally, afford to write this code, and we can write much more of it.

GREENFIELDBOYCE: This company now uses so much DNA, it not only makes its own but also buys some from another manufacturer named Twist Bioscience. Its CEO is Emily Leproust. She says her company's other customers are pharmaceutical¹³ firms, agricultural companies and academic scientists trying to understand basic biology. Anyone can just order DNA online.

EMILY LEPROUST: So you log on the website, you upload the sequence you want and you can order one gene² or 10 genes or a thousand genes.

GREENFIELDBOYCE: A couple weeks later, your custom DNA arrives in the mail. At least, it does if your order gets through this company's rigorous security screening. Because here's the thing - DNA is so powerful that it's potentially dangerous. Someone could use it to transform a harmless bacteria into one that makes a deadly toxin¹⁴. And bits of DNA can be assembled into a virus, like Ebola. Twist director of biosecurity is James Diggans. He says they check out every potential customer and each requested DNA sequence, looking to see if there's anything worrisome in there, like a gene specific to some nasty germ.

JAMES DIGGANS: And then we make a decision about whether that sequence is appropriate to make for that customer.

GREENFIELDBOYCE: A handful of times, they've said no. Diggans won't give specifics. He does say they would not have made the pieces of DNA that one research team recently ordered from a different company and used to assemble the horsepox virus. This was controversial because horsepox is so close to the deadly human pathogen smallpox¹⁵.

DIGGANS: That is not something we would have been comfortable in producing.

GREENFIELDBOYCE: This just illustrates¹⁶ a key issue - companies have different standards. Many, but not all, follow some biosecurity guidelines put out by the U.S. government that were designed to keep people from doing anything dodgy.

Those guidelines came out about a decade ago and are kind of out of date. For example, the guidelines call for screening only big chunks¹⁷ of DNA. Diggans says, it's gotten so easy to put little pieces together, they really need to be screened as well.

DIGGANS: And so we think that's sort of an easy next step that the U.S. government could take.

GREENFIELDBOYCE: There's also new desktop¹⁸ DNA synthesizers. Rather than ordering from a company, scientists can now buy one of these machines to create desired bits of DNA in their own lab.

DIGGANS: That machine needs to be able to screen and ensure that that manufacture occurs safely and legally.

GREENFIELDBOYCE: Just like photocopier¹⁹ machines have built-in controls to stop people from counterfeiting²⁰ money.

Gigi Gronvall is a biosecurity expert at the Center for Health Security at Johns Hopkins University. She agrees that the government should strengthen its guidelines and thinks all researchers who receive federal funding should be required to order their synthetic²¹ DNA from companies that follow them.

GIGI GRONVALL: The idea there is to level the playing field, so to make the business case that screening is not a burden for the companies, it becomes an advantage.

GREENFIELDBOYCE: Still, she says, these measures are only a partial solution.

GRONVALL: It's going to be something that should be done to deter²² some people who might misuse⁴ these technologies. It's not going to get everybody.

GREENFIELDBOYCE: Just because the technology is advancing rapidly and is available around the world.

A spokesperson for the Department of Health and Human Services said that officials are in the process of reviewing and updating the guidelines for synthetic DNA manufacturers but that it was too early to discuss what changes might be made.

Nell Greenfieldboyce, NPR News.

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1 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。

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 misuse   

n.误用，滥用；vt.误用，滥用

参考例句：

• It disturbs me profoundly that you so misuse your talents.你如此滥用自己的才能，使我深感不安。
• He was sacked for computer misuse.他因滥用计算机而被解雇了。

5 misused   

v.使用…不当( misuse的过去式和过去分词 )；把…派作不正当的用途；虐待；滥用

参考例句：

• He misused his dog shamefully. 他可耻地虐待自己的狗。 来自《简明英汉词典》
• He had grossly misused his power. 他严重滥用职权。 来自《简明英汉词典》

6 byline   

n.署名；v.署名

参考例句：

• His byline was absent as well.他的署名也不见了。
• We wish to thank the author of this article which carries no byline.我们要感谢这篇文章的那位没有署名的作者。

7 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

8 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

9 yeast   

n.酵母；酵母片；泡沫；v.发酵；起泡沫

参考例句：

• Yeast can be used in making beer and bread.酵母可用于酿啤酒和发面包。
• The yeast began to work.酵母开始发酵。

10 fungi   

n.真菌，霉菌

参考例句：

• Students practice to apply the study of genetics to multicellular plants and fungi.学生们练习把基因学应用到多细胞植物和真菌中。
• The lawn was covered with fungi.草地上到处都是蘑菇。

11 literally   

adv.照字面意义，逐字地；确实

参考例句：

• He translated the passage literally.他逐字逐句地翻译这段文字。
• Sometimes she would not sit down till she was literally faint.有时候，她不走到真正要昏厥了，决不肯坐下来。

12 automated   

a.自动化的

参考例句：

• The entire manufacturing process has been automated. 整个生产过程已自动化。
• Automated Highway System (AHS) is recently regarded as one subsystem of Intelligent Transport System (ITS). 近年来自动公路系统(Automated Highway System,AHS)，作为智能运输系统的子系统之一越来越受到重视。

13 pharmaceutical   

adj.药学的，药物的；药用的，药剂师的

参考例句：

• She has donated money to establish a pharmaceutical laboratory.她捐款成立了一个药剂实验室。
• We are engaged in a legal tussle with a large pharmaceutical company.我们正同一家大制药公司闹法律纠纷。

14 toxin   

n.毒素，毒质

参考例句：

• Experts have linked this condition to a build-up of toxins in the body.专家已把这一病症与体内毒素的积累联系起来。
• Tests showed increased levels of toxin in shellfish.检验表明水生有壳动物的毒素水平提高了。

15 smallpox   

n.天花

参考例句：

• In 1742 he suffered a fatal attack of smallpox.1742年，他染上了致命的天花。
• Were you vaccinated against smallpox as a child?你小时候打过天花疫苗吗？

16 illustrates   

给…加插图( illustrate的第三人称单数 )； 说明； 表明； （用示例、图画等）说明

参考例句：

• This historical novel illustrates the breaking up of feudal society in microcosm. 这部历史小说是走向崩溃的封建社会的缩影。
• Alfred Adler, a famous doctor, had an experience which illustrates this. 阿尔弗莱德 - 阿德勒是一位著名的医生，他有过可以说明这点的经历。 来自中级百科部分

17 chunks   

厚厚的一块( chunk的名词复数 )； （某物）相当大的数量或部分

参考例句：

• a tin of pineapple chunks 一罐菠萝块
• Those chunks of meat are rather large—could you chop them up a bIt'smaller? 这些肉块相当大，还能再切小一点吗？

18 desktop   

n.桌面管理系统程序；台式

参考例句：

• My computer is a desktop computer of excellent quality.我的计算机是品质卓越的台式计算机。
• Do you know which one is better,a laptop or a desktop?你知道哪一种更好，笔记本还是台式机？

19 photocopier   

n.复印机

参考例句：

• You've left your master in the photocopier.你把原件留在影印机里了。
• If the photocopier stops working,just give it a clout.如果那部影印机停止运转的话就敲它一下。

20 counterfeiting   

n.伪造v.仿制，造假( counterfeit的现在分词 )

参考例句：

• He was sent to prison for counterfeiting five-dollar bills. 他因伪造5美元的钞票被捕入狱。 来自辞典例句
• National bureau released securities, certificates with security anti-counterfeiting paper technical standards. 国家质量技术监督局发布了证券、证件用安全性防伪纸张技术标准。 来自互联网

21 synthetic   

adj.合成的，人工的；综合的；n.人工制品

参考例句：

• We felt the salesman's synthetic friendliness.我们感觉到那位销售员的虚情假意。
• It's a synthetic diamond.这是人造钻石。

22 deter   

vt.阻止，使不敢，吓住

参考例句：

• Failure did not deter us from trying it again.失败并没有能阻挡我们再次进行试验。
• Dogs can deter unwelcome intruders.狗能够阻拦不受欢迎的闯入者。