VOA标准英语2008年-Australian, US Scientists Bring Extinct Gene Ba

By Phil Mercer
Sydney
21 May 2008

Australian and U.S. scientists have successfully inserted a gene¹ from the extinct Tasmanian tiger into a mouse embryo². They say the result has been bone and cartilage from the extinct marsupial³ developing inside the embryo. From Sydney, Phil Mercer reports.

The last known Tasmanian tiger or thylacine, died in a Zoo in Australia's southern island state in 1936. The dog-sized marsupial carnivore was hunted to extinction⁴ early in the last century.

The scientists extracted DNA⁵ - genetic⁶ material - from a 100-year-old specimen⁷ that had been preserved in a museum, and injected it into a mouse embryo.

The nine-year project was the work of a joint⁸ research team from universities in Melbourne, Australia, and Texas in the United States.

They watched as thylacine bone and cartilage began to grow in the embryo.

Turning a museum relic⁹ into a living creature is currently not possible and those expecting the cloning of an entire animal from an extinct species are likely to be disappointed.

But scientist Andrew Pask from the University of Melbourne says the results could lead to experiments that answer questions about the bodies of other extinct species.

"So, any extinct species at all that has some intact DNA left, you can then use this technique to actually examine the function of the genes¹⁰ contained within that genome," Pask explained. "So, there is a lot of DNA available from mammoth¹¹ and Neanderthal that you could potentially use this technique now to examine exactly how those genes may have functioned."

This is the first time that DNA from an extinct species has been used to grow tissue and bone in a living animal.

The technique could be used to reactivate individual genes from other long-lost creatures, including dinosaurs¹².

Their genes could be transplanted into living animals to determine, for example, what their skin looked like or whether they were warm or cold blooded.

There could also be practical applications for humans. The researchers on this project think their discoveries have the potential to create new cancer-fighting medicines.

1 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。

2 embryo   

n.胚胎，萌芽的事物

参考例句：

• They are engaging in an embryo research.他们正在进行一项胚胎研究。
• The project was barely in embryo.该计划只是个雏形。

3 marsupial   

adj.有袋的，袋状的

参考例句：

• Koala is an arboreal Australian marsupial.考拉是一种澳大利亚树栖有袋动物。
• The marsupial has been in decline for decades due to urban sprawl from car accidentsdog attacks.这种有袋动物其数量在过去几十年间逐渐减少,主要原因是城市的扩张、车祸和狗的袭击。

4 extinction   

n.熄灭，消亡，消灭，灭绝，绝种

参考例句：

• The plant is now in danger of extinction.这种植物现在有绝种的危险。
• The island's way of life is doomed to extinction.这个岛上的生活方式注定要消失。

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 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。

7 specimen   

n.样本，标本

参考例句：

• You'll need tweezers to hold up the specimen.你要用镊子来夹这标本。
• This specimen is richly variegated in colour.这件标本上有很多颜色。

8 joint   

adj.联合的，共同的；n.关节，接合处；v.连接，贴合

参考例句：

• I had a bad fall,which put my shoulder out of joint.我重重地摔了一跤，肩膀脫臼了。
• We wrote a letter in joint names.我们联名写了封信。

9 relic   

n.神圣的遗物，遗迹，纪念物

参考例句：

• This stone axe is a relic of ancient times.这石斧是古代的遗物。
• He found himself thinking of the man as a relic from the past.他把这个男人看成是过去时代的人物。

10 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

11 mammoth   

n.长毛象；adj.长毛象似的，巨大的

参考例句：

• You can only undertake mammoth changes if the finances are there.资金到位的情况下方可进行重大变革。
• Building the new railroad will be a mammoth job.修建那条新铁路将是一项巨大工程。

12 dinosaurs   

n.恐龙( dinosaur的名词复数 )；守旧落伍的人，过时落后的东西

参考例句：

• The brontosaurus was one of the largest of all dinosaurs. 雷龙是所有恐龙中最大的一种。 来自《简明英汉词典》
• Dinosaurs have been extinct for millions of years. 恐龙绝种已有几百万年了。 来自《简明英汉词典》