VOA慢速英语20060404a

AGRICULTURE REPORT - Scientists Clone Pigs to Make Omega-3 Fatty AcidsBy Mario Ritter

Broadcast: Tuesday, April 04, 2006

I'm Faith Lapidus with the VOA Special English Agriculture Report.

Scientists say they have developed pigs that produce omega-three fatty acids. These fatty acids are believed to help fight heart disease. But it could be some time before these experimental pigs go to market.

The animals are clones, genetic² copies of each other. The Food and Drug Administration has never approved a cloned animal for use as food. Still, some people believe Americans might someday buy the new pork if they see it as heart-healthy.

Professor Jing Kang at Harvard Medical School took the first step in the work that led to the cloned pigs. His research suggests that no mammal naturally produces omega-three fatty acids. So Doctor Kang genetically³ engineered mice with a gene¹ that can create them from another fatty acid.

He took the gene from a kind of small worm that scientists have studied for years. Doctor Kang published his findings with two other researchers in two thousand four.

This research led the way for Randall Prather at the University of Missouri to clone pigs that can do the same thing. Pigs have been cloned before, but not for a purpose like this. Last month, Nature Biotechnology published a report describing how the experiment was done. Seventeen scientists took part in the study.

Fatty acids are the building materials of fat. Omega-three fatty acids are believed to reduce the risk of heart disease. They are also thought to reduce levels of harmful cholesterol⁴ in the blood.

The human body can make most kinds of fat by itself out of sugars. But it cannot make omega-three or omega-six fatty acids. These must come from foods or dietary supplements.

But it is still not clear how soon genetically engineered animals might be approved for Americans to eat. Some people would have no concerns about eating meat produced through biotechnology. Others, though, say they see the idea as a step too far removed from nature.

This new research is aimed at producing pigs with a healthier form of fat.

Fat gives flavor. But in the United States, pork producers have cut the fat, hoping to appeal to people worried about heart disease. Twenty years ago the industry launched a marketing⁵ campaign comparing pork to chicken. It called pork the other white meat.

Now the National Pork Board has a new marketing campaign. The aim is to get Americans to think of pork as a way to add a little excitement to dinner. The message: Don't be blah. This VOA Special English Agriculture Report was written by Mario Ritter. I'm Faith Lapidus.

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 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。

3 genetically   

adv.遗传上

参考例句：

• All the bees in the colony are genetically related. 同一群体的蜜蜂都有亲缘关系。
• Genetically modified foods have already arrived on American dinner tables. 经基因改造加工过的食物已端上了美国人的餐桌。 来自英汉非文学 - 生命科学 - 基因与食物

4 cholesterol   

n.（U）胆固醇

参考例句：

• There is cholesterol in the cell of body.人体细胞里有胆固醇。
• They are determining the serum-protein and cholesterol levels.他们正在测定血清蛋白和胆固醇的浓度。

5 marketing   

n.行销，在市场的买卖，买东西

参考例句：

• They are developing marketing network.他们正在发展销售网络。
• He often goes marketing.他经常去市场做生意。