VOA标准英语2010年-New Era for Human Genetics Begins

An international effort to build a detailed¹ map of human genetic³ variation has completed its pilot phase and could shape a new understanding of human evolution and may help in fighting disease.

 
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The 1000 Genomes Project aims to sequence the genetic code of 2,500 people.
A decade ago, scientists made worldwide headlines when they announced they had sequenced the human genome - made a kind of map, in other words, of DNA⁴, the inherited molecule⁵ that makes us human. But that was only one genome. Everyone on Earth has a unique genetic makeup⁶, and researchers have now sequenced thousands of individuals' DNA.

The first effort to sequence the human genome came in under budget and ahead of schedule, and the process has gotten progressively cheaper and faster.

"In the last 10 years," said Richard Durbin, co-chair of the 1000 Genomes Project. "DNA sequencing technology has advanced dramatically so it has become feasible to systematically⁷ sequence many people to find genetic variants⁸, and build a catalog which we can use as a basis for investigations⁹ into disease, genetics, and which variants may be functional¹⁰."

 
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Genetic variations are the way your genes¹¹ differ from other people's. Some variations relate to differences we can see, like eye color. Others may put us at greater risk for disease. Some variations are inherited. Others can be caused by toxic¹² chemicals or radiation or simply by mistakes in copying DNA.

Most genetic variations are found in lots of unrelated people. Scientists have started to investigate possible links between disease and some of these variations, called single nucleotide polymorphisms, or SNPs. The researchers aim to probe deeper.

"The 1000 Genomes Project makes this approach much more complete and much more powerful," said David Altschuler, 1000 Genomes co-chair, "by going down to much lower frequencies, and also broader range of populations and more complete data in each frequency range and each population."

At the University of Washington in Seattle, meanwhile, Evan Eichler and his colleagues have been using a technique to identify pieces of the genome that duplicate other parts of the DNA code. Writing in the journal Science, the researchers describe how they identified more than four million places where they found these duplicates, called copy-number variants.

Eichler says these variants could help identify genes that may be associated with disease that are what he called "inaccessible¹³" using other techniques. He also said it can help improve the understanding of human evolution.

"We think the veil has been lifted for us in terms of a whole new level of genetic diversity. And when we compare these roughly 159 humans that we've analyzed¹⁴ to date, and compared variations they've found in their genomes to that of the great apes, we have the ability, I think pretty clearly, to identify the genes and the gene² families which have expanded specifically in our lineage of evolution since we separated from that of chimpanzee and gorilla," Eichler said.

Back at the 1000 Genomes project, co-chair David Altshuler says the organization's work will provide data so scientists can answer questions about the role genes play in health based on facts, not guesswork. "And so rather than speculate," he said, "I think we'd say we are helping¹⁵ to create the foundation to answer that question, and anyone who does speculate, I think is speculating."

By the way, the goal of the 1000 Genomes project isn't to sequence the genetic code of exactly 1,000 people. Instead, the aim is to identify genetic variations that occur in at least one out of every 100 people or one percent. In particular, that will require using genetic material from many thousands of people from all over the world. And it will need to include a lot more geographic¹⁶ diversity. Only a handful of genomes from Latin America and Africa have been sequenced so far.
 

1 detailed   

adj.详细的，详尽的，极注意细节的，完全的

参考例句：

• He had made a detailed study of the terrain.他对地形作了缜密的研究。
• A detailed list of our publications is available on request.我们的出版物有一份详细的目录备索。

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 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。

5 molecule   

n.分子，克分子

参考例句：

• A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。
• This gives us the structural formula of the molecule.这种方式给出了分子的结构式。

6 makeup   

n.组织；性格；化装品

参考例句：

• Those who failed the exam take a makeup exam.这次考试不及格的人必须参加补考。
• Do you think her beauty could makeup for her stupidity?你认为她的美丽能弥补她的愚蠢吗？

7 systematically   

adv.有系统地

参考例句：

• This government has systematically run down public services since it took office.这一屆政府自上台以来系统地削减了公共服务。
• The rainforest is being systematically destroyed.雨林正被系统地毀灭。

8 variants   

n.变体( variant的名词复数 )；变种；变型；（词等的）变体

参考例句：

• Those variants will be preserved in the'struggle for existence". 这些变异将在“生存竞争”中被保留下来。 来自辞典例句
• Like organisms, viruses have variants, generally called strains. 与其他生物一样，病毒也有变种，一般称之为株系。 来自辞典例句

9 investigations   

（正式的）调查( investigation的名词复数 )； 侦查； 科学研究； 学术研究

参考例句：

• His investigations were intensive and thorough but revealed nothing. 他进行了深入彻底的调查，但没有发现什么。
• He often sent them out to make investigations. 他常常派他们出去作调查。

10 functional   

adj.为实用而设计的，具备功能的，起作用的

参考例句：

• The telephone was out of order,but is functional now.电话刚才坏了，但现在可以用了。
• The furniture is not fancy,just functional.这些家具不是摆着好看的，只是为了实用。

11 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

12 toxic   

adj.有毒的，因中毒引起的

参考例句：

• The factory had accidentally released a quantity of toxic waste into the sea.这家工厂意外泄漏大量有毒废物到海中。
• There is a risk that toxic chemicals might be blasted into the atmosphere.爆炸后有毒化学物质可能会进入大气层。

13 inaccessible   

adj.达不到的，难接近的

参考例句：

• This novel seems to me among the most inaccessible.这本书对我来说是最难懂的小说之一。
• The top of Mount Everest is the most inaccessible place in the world.珠穆朗玛峰是世界上最难到达的地方。

14 analyzed   

v.分析( analyze的过去式和过去分词 )；分解；解释；对…进行心理分析

参考例句：

• The doctors analyzed the blood sample for anemia. 医生们分析了贫血的血样。 来自《简明英汉词典》
• The young man did not analyze the process of his captivation and enrapturement, for love to him was a mystery and could not be analyzed. 这年轻人没有分析自己蛊惑著迷的过程，因为对他来说，爱是个不可分析的迷。 来自《简明英汉词典》

15 helping   

n.食物的一份&adj.帮助人的，辅助的

参考例句：

• The poor children regularly pony up for a second helping of my hamburger. 那些可怜的孩子们总是要求我把我的汉堡包再给他们一份。
• By doing this, they may at times be helping to restore competition. 这样一来, 他在某些时候,有助于竞争的加强。

16 geographic   

adj.地理学的，地理的

参考例句：

• The city's success owes much to its geographic position. 这座城市的成功很大程度上归功于它的地理位置。 来自《简明英汉词典》
• Environmental problems pay no heed to these geographic lines. 环境问题并不理会这些地理界限。 来自英汉非文学 - 环境法 - 环境法