Unit 8 Is biotechnology our friend or enemy?

II. Basic Listening Practice

1.    Script                                                                             

M: Scientists claim the world population has 99.5% of the same DNA.

W: But this doesn’t tell us there is no such thing as race.

Q: What is true of the DNA of difference races?

2.    Script

W: With the advent of the genetic map we know where everything is, but do we know where to go with it?

M: Your map seems to differ largely from my geographical map!

Q: What does the man imply?

3.    Script

M: As you know, it has taken millions of years of evolution and natural selection to get us where we are today.

W: Yes, but now that we have genetic engineering, we seem to have decided that we want to be God.

Q: What does the woman imply?

4.    Script

M: I think the research into cloning will lead us into dangers, filling us with false hopes of perfection.

W: It’s too late to turn back the clock. We’ll just have to depend on common sense to solve uncommon problems.

Q: What does the woman mean?

5.    Script

W: In America, many prisoners are having their cases reviewed, and some have even been freed through DNA testing.

M: Except for the ones whose death sentence has already been carried out.

Q: What can we learn about DNA testing from the dialog?

 

III. Listening In

Task 1: Stem Cell Research

Script

Gregory: The Republican Party in America is opposing stem cell research. I find it

       hard to believe that in this day and age, someone would do that.

Lillian: Stem cell research sounds pretty impressive, I’ll admit. But just what is it?

Gregory: Well, a stem cell is a special type of cell. It is a general cell that, when it

       devides, can become any specific type of cell.

Lillian: You mean, a stem cell can become a heart cell? Or a brain or a kidney cell?

Gregory: That’s about it. Stem cells are a part of the body’s maintenance and repair

       system. When they divide, they can become any cell type.

Lillian: I guess there would be some tremendous medical advantages in that sort of

      research.

Gregory: You’ve said a mouthful. Recently, scientists were able to help a man who

       lost a jawbone for cancer. They recreated bone material for his jaw from stem cells. What it means is that since the new bone was created out of the person’s own cells, there was no problem with rejection because the DNA was the same.

Lillian: I bet the person was delighted. Why would anyone oppose that sort of research? It would seem to have endless potential to benefit the human race.

Gregory: I agree, but there are people who think we should not interfere with nature and manipulate “what is natural”.

Lillian: It’s easier to hold such a narrow view if you’re not in a position to need the benefits of the research. If you’re missing a jawbone because of cancer, you probably support the research.

 

Task 2: The Improvement of Rice

Script      

Scientists now know a lot more about a grain that people have eaten for ten thousand years. (S1) Research teams around the world have completed a map of the (S2) genes of rices. The findings appeared last week in the (S3) journal Nature.

The aim is to speed up the improvement of rice. The scientists (S4) warn that the kinds of rice plants used now have reached the limit of their (S5) productivity. Yet world rice production must (S6) grow by an estimated 30 percent in the next twenty to meet demand. By 2025, as many as 4.6 billion people will depend on rice for (S7) survival. There is a lot of pressure on breeders to improve the crop, and the rice genome is a valuable tool to do that. (S8) Plant breeders have already used preliminary information from the rice genome to create experimental strains of rice that better resist cold and pests.

The researchers also say rice is an excellent choice for genetic mapping and engineering. Rice genes have only about 390 million chemical bases. That maight sound like a lot. But other major food grains have thousands of millions. (S9) The new map could better explain more than just rice. Rice shares a common ancestor with other cereal crops. Because rice is the first cereal crop to be fully analyzed, researchers expect that sufficient knowledge of its genetic information will reveal the heredity of more complex grains, including corn, wheat and barley.

(S10) While significant progress has been made in the analysis of the rice genome, the mapping of human genes is also making headway. When scientists can identify and manipulate genes that cause certain diseases, mankind will cure them easily. The human genetic map may help us control a person’s height, weight, appearance and even length of life.

 

 

Task3: Human Cloning

Human cloning is the creation of a genetically identical copy of an existing or previously existing human. The term is generally used to refer to artificial human cloning. Human clones in the form of identical twins are commonplace, with their cloning occurring during the natural process of reproduction. There are two commonly discussed types of human cloning: therapeutic cloning and reproductive cloning. Therapeutic cloning would involve cloning adult cells for use in medicine and is an active area of research. Reproductive cloning would involve making clones human. A third type of cloning called replacement cloning is a theoretical possibility, and would be a combination of therapeutic and reproductive cloning. Replacement cloning would entail the replacement of an extensively damaged, failed, or failing body through cloning followed by whole or particle brain transplant.

The various forms of human cloning are controversial. There have been numerous demand for all progress in the human cloning field to be halted. Most scientific, governmental and religious organizations oppose reproductive cloning. The American Association for the advancement of Science and other scientific organizations have made public statements, suggesting that human reproductive cloning be banned until safety issues are resolved. Serious ethical concerns have been raised in view of the future possibility by harvesting organs from clones. Some people have considered the idea of growing organs separately from a human body. In this way, a new organ supply could be established without the moral problem of harvesting organs from humans. Research is also being done on the idea of growing organs that are biologically acceptable to the human body inside of animals such as pigs or cows, and then transplanting them to humans.

 

IV. Speaking Out

MODEL 1   Why are people protesting against

             genetically modified foods?

Susan: With so many people suffering from malnutrition around the world, why are people protesting against genetically modified foods?

Chris: Some people are protesting about genetically modified foods, but even more people are protesting the fact that processed foods containing these ingredients aren’t labeled.

Susan: But why should they be labeled?

Chris: Not everyone is sure that genetically modified foods are safe. They want to be certain that biotech foods have the sme composition as organic foods.

Susan: But there are more urgent problems in this world. Many people are dying of starvation.

Chris: But those who aren’t starving may want genetically modified foods to be labeled so they know what foods they should andd shouldn’t eat.

Susan: You know, I heard of a genetically modified fish that grew to be ten times its normal size.

Chris: That sure sounds abnormal.

Susan: Yeah, it does sound a bit strange , but that fish could feed ten times as many people.

Chris: You’re right; genetically modified food might help solve world hunger. But I think we have a right to know what we are eating.

 

 

MODEL2   Do you think the cloning of humans

            should be forbidden by law?

Script

Susan: After the cloning of Dolly the sheep, I think human cloning is next.

John: Whoa. I have some reservations about it. There are stll many scientific problems 

     to solve before human cloning starts.

Susan: There’s an easier way. The Clonaid Company says they’ve cloned humans.

John: Oh, my God! These guys claim aliens from another planet taught them human

cloning.

Susan: A woman gave them half a million dollars to clone her dead daughter.

John: Clearly that woman doesn’t know much about cloning. How risky it is!

Susan: I know it’s inefficient. It took 276 tries to produce Dolly. But why is it risky?

John: Cloned animals grow abnormally large and age unnaturally fast.

Susan: In other words, that woman may not be happy with her cloned daughter.

John: Then there are the emotions. No one knows if cloning damages the mind.

Susan: Do you think the cloning of humans should be forbidden by law?

John: To my mind, the cloning of human organs shouldn’t be prohabited. It may help 

     solve medical problems.

Susan: I see your point: cloning should be regulated if it’s to benefit humanity.

 

 

MODEL3   Is it interfering with nature?

Script

Nora: Some religious groups are opposed to genetic research. They believe it’s interfering with nature.

John: I know. But nature can be pretty hard-nosed too, so we often need to interfere with her—we build dams to control flooding.

Nora: There’re many diseases that are a part of nature, and they cause people a great deal of misery: cancer and diabetes, for example.

John: A better understanding of the genetic code that controls our body would be a great help in curing many diseases.

Nora: The project to map the human genetic code…what’s that called?

John: The genome project. As you say, it has tremendous promise to make our lives better—just in the ability to identify and correct genetically-caused diseases like Alzheimer’s.

Nora: Some diseases like cancer are also believed to have a genetic switch.

John: That’s right, and once researchers identify the switch, perhaps they can turn off cancer or Alzheimer’s.

Nora: People are also concerned that science will enable us to determine such qualities as intelligence and height.

John: You know it’s going to happen—it’s just a matter of when.

Nora: Imagine if everyone was a combination of Yao Ming and Albert Einstein.

John: But what if they get it wrong, and you wind up with Yao Ming’s knowledge of nuclear physics and Albert Einstein’s height?

Nora: All those religious groups would say that it served you right.

 

 

V. Let’s Talk

VI.  Further Listening and Speaking

Task1: An interview with a professor

Script

Correspondent: In the U.S. what percentage of people support biotech crops? And do those who support biotech crops also eat biotech foods? What percentage of food on the market has genetically modified ingredients?

Professor:   U.S. consumers have been exposed to a very effective anti-biotechnology propaganda campaign for the last few years, but according to polls, over 70% support biotechnology. For example, in a recent referendum in Oregon, voters rejected a proposal to require special labels on all products containing biotech ingredients by an overwhelming 73% to 27%. That’s probably because consumers know that we have an effective administrative system. Many may also know that 70-80% of the processed food products on supermarket shelves contain one or more ingredients from biotech crops. All Americans eat biotech foods unless they deliberately seek out products that are labeled otherwise. Evidence suggests that this is less than 5% of consumers.

Correspondent: Chinese scientists have used biotechnology to create a new type of tomato, which contains the vaccine against hepatitis B. What’s your take on this?

Professor:     It’s a great example of how this technology can be used to save lives, ease pain and suffering and improve the human condition. How can anyone be opposed to that? My only hope is that the clinical trials of this new tomato go well, and that it is quickly delivered to health-care providers who will use it to vaccinate people against hepatitis. By the way, please note that I do think that such new pharmaceutical foods need to be handled as medicines by professionals and not as conventional foods. You will never see these tomatoes in the supermarket. In a sense, the tomato plant is just being used to manufacture a vaccine in a very safe and economical manner.

 

Task 2: Is it moral to clone humans?

Script

Laura: Did you hear about that peculiar cult that claimed to have created the world’s first human clone?

Ian:   Yeah, I did! They also said that it was aliens that created life on earth over 25,000 years ago. What are they on?

Laura: I know! It was so obviously just part of an elaborate hoax to bring publicity to their crazy movement. But I don’t think the truth can be far off. Scientists have been working on it for years.

Ian:   Sure, but most scientists are working on cloning human cells or body parts that can be used to repair or replace damaged organs. Not complete human beings! That’s just science fiction!

Laura: Well, the science may seem to be very advanced, but the idea is not a new one. In A Journey to the West, Sun Wu-kung, the Monkey King, can clone himself from the hairs on his head. He just plucks a few hairs, chews them a bit, and when he spits them out, they change into replicas of him!

Ian:   Really? Now that would be cool! You could send your clone to school while you went to the cinema, and then it could do your homework! Wow! Now that I think of it, it would be kind of fun to have a clone!

Laura: You would say that! Don’t you think it’s slightly immoral? I mean, it’s just like having a slave. Doesn’t the clone deserve a life of his own?

Ian:   Sure, but human beings must learn to strike a balance between the welfare of a patient and of a clone.

 

 

Task3:  Scanning diseases with a gene map

A large analysis of the genes of 6,200 ethnic Chinese has revealed subtle genetic difference between inhabitants in northern China and southern China.

Published in the American Journal of Human Genetics, the study is important as scientists are trying to identify whether certain gene variants may render some people more vulnerable to some diseases. Then preventative measures can be taken and therapies may one day be found.

Led by Liu Jianjun, head of the human genetics group at the agency for Science, Technology and Research in Singapore, the researchers found that inhabitants in northern China were genetically distinguishable from those in the south, a finding that was consistent with historical migration patterns in China.

In a telephone interview, Liu told Reuters, “This genetic map tells us how people differ from each other, or how people are more closely linked to each other. We don’t know what these variants are responsible for. Some may have clinical outcomes and influence disease development. That is why we are interested in genetic variation. That will help us understand diseases.”

The huge sample of 8,200 ethnic Chinese participants was drawn from 10 Chinese provinces and Singapore.

The team has since moved onto the second stage of research to try to establish if these gene variants may be linked to the tendency among certain groups of Chinese to develop particular diseases such as nasopharyngeal cancer. This kind of cancer is far more prevalent among southern Chinese than among northern Chinese.

By comparing 1,000 patients and 1,000 people without the cancer, the scientists have identified genetic variants at three positions in the genetic map. These variants can provide information by certain people tend to suffer from the cancer.