1 A Genetically Modified Solution? Th e u n i t e d n a t i o n s World Food Program has clearly stated, Hunger

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1 1 A Genetically Modified Solution? Th e u n i t e d n a t i o n s World Food Program has clearly stated, Hunger and malnutrition are in fact the number one risk to health worldwide greater than AIDS, malaria, and tuberculosis combined. 1 2 billion hungry More than 1 billion people in the world today don t get enough nutritious food to lead healthy lives. As shown in the figure at right, this means that more than one in seven people are hungry or malnourished. Widespread sustainable farming practices and broader distribution of food would help meet nutritional needs and promote economic and social well-being of huge numbers of the world s hungry people. Beginning in 1945, a private program in the United States started developing fast-growing, high-yield rice and wheat seeds and new fertilizers to help other countries grow enough food for their people. Results in Mexico, India, and Pakistan were so successful that in the 1960s the new farming practices became known as the Green Revolution. Those methods, however, included heavy use of fertilizers and pesticides, which caused water pollution and other environmental problems. Today, there is a call for new ways to improve crop yields while not harming the environment. Some people think that genetically modified (GM) crops provide a good solution. Hunger is one of the world s greatest sustainability challenges today. To create genetically modified organisms (often called GMOs) scientists directly manipulate the genes of an organism, often by inserting or deleting one or more genes. The inserted gene is usually from another species. The purpose of this manipulation is to give the target organism and its offspring a new trait that improves it in some way. The improvement might, for example, give the organism higher vitamin content. The process is called genetic engineering. Corn crop yield increased dramatically during the Green Revolution. 261

2 Science & Global Issues/Biology genetics In the late 1990s, a few countries, including the United States and Brazil, began allowing farmers to grow genetically modified crops. Many other countries, however, were uncertain about the impacts the GMOs might have on human health, the environment, and unmodified crops, and have tightly restricted their import or growth. For example, GMOs have been highly restricted in Japan and several European Union countries. Today, as populations everywhere are growing and needing more food, some governments are considering changing their policies on the growing and importing of genetically modified organisms. You are advising a country where many people suffer hunger. Corn is an important crop in that country for feeding both people and the animals they rely on for other foods. You have been called to meet with the country s Government Office of Agriculture, which has set up a committee to discuss allowing farmers to raise genetically modified crops. Today, you will examine evidence presented by a scientific panel that evaluated the benefits and risks of growing a genetically modified corn, called Bt corn. a This corn (a) has been modified with a gene from these bacteria (b) to produce an insecticide. b 262

3 A Genetically Modified Solution? Activity 1 Challenge 00Should your country allow farmers to grow genetically modified corn? Materials For each group of four students sheet of chart paper 2 markers of different colors For each student Student Sheet 1.1, Genetically Modified Corn: Potential Benefits and Risks Procedure 1. Read the background information about Bt corn on the next page. 2. When you finish reading, record in your science notebook the two or three questions about Bt corn that you would most like to have answered before you advise this country about growing Bt corn. 3. With your group, review all of your questions, and select the three or four that you think are most important. Record these questions on the top half of the chart paper. 4. With your group, decide who will read which one of the statements on the following pages made by the science panel members. Take turns reading your statements aloud to your group. 5. After each statement is read, record on Student Sheet 1.1, Genetically Modified Corn: Potential Benefits and Risks, any benefits or risks mentioned in the statement. 6. Based on the information the scientific panel provided, decide if you would support growing genetically modified corn in this country. Be sure to consider the statements from all four scientists. In your science notebook, record your opinion and the evidence and your thinking that led you to your opinion. 7. Share your ideas with the class by conducting a walking debate. Your teacher will explain how to run the debate. 8. With your group, review the questions you listed on the chart you made for Step 3. Check which of those questions have been answered. With another colored pen, add to your chart three or four new questions you have about genetically modified corn and other genetically modified organisms. Be prepared to share any answers you found for your previous questions and your new questions with the class. 263

4 Science & Global Issues/Biology genetics background information Bt Corn c o m m o n s o i l b a c t e r i a called Bacillus thuringeinsis (Bt) produce a protein toxic to the larvae of certain insects, such as the European corn borer. This insect is found throughout Europe, North Africa, Canada, and most of the United States. A single generation of corn borers can reduce by as much as 5% the amount of corn a farm produces. In warm climates up to three generations of corn borers will attack a crop during one growing season, which causes an even greater percentage of crop loss. In the past, many farmers have sprayed chemical insecticides that kill corn borers and many other insects. Many of these insecticides pose health risks to farm workers, consumers, and bees and other beneficial insects. Also, the insecticides are expensive to buy and to spray on crops. Beginning in Europe in the 1930s, farmers in many regions of the world have sprayed Bt bacteria on fields of plants as an insecticide. The Bt toxin is generally considered safe for people and wildlife. Its drawbacks are that it remains active for no more than a week after it is applied, and it is not effective against all insects. In 1996, farmers in the United States began growing a new The adult corn borer is a moth (a). The corn borer larvae bore into the plant and destroy the corn (b). a b 264

5 A Genetically Modified Solution? Activity 1 genetically modified corn plant, called Bt corn. This corn plant had the Bt gene from Bacillus thuringeinsis inserted into its cells. This gene provides information that causes the plant cells themselves to produce the Bt protein. As a result, the offspring of the modified plants are protected from the corn borer. Today, genetically modified corn is one of four genetically modified crops along with canola, cotton, and soybeans grown in huge quantities. The table below shows the top 10 countries that grow genetically modified crops, which crops they grow, and on how much land. Today, the need for more food to meet the needs of growing populations has led many countries to consider growing genetically modified crops as a way to increase the amounts grown. People in various countries fear that such crops might harm humans, other organisms, and the environment. These concerns have led to debate about which is greater: the benefits or risks of genetically modified organisms. n Top 10 Countries Growing Genetically Modified Crops in 2008 Country Type of crop Area (millions of hectares) United Sates soybean, corn (maize), cotton, canola, squash, papaya, alfalfa, sugar beet 62.5 Argentina soybean, corn (maize), cotton 21.0 Brazil soybean, corn (maize), cotton 15.8 India cotton 7.6 Canada canola, corn (maize), soybean, sugar beet 7.6 China cotton, tomato, poplar, petunia, papaya, sweet pepper Paraguay soybean 2.7 South Africa corn (maize), soybean, cotton 1.8 Uruguay soybean, corn (maize) 0.7 Bolivia soybean 0.6 s o u r c e : International Service for the Acquisition of Agri-biotech Applications Brief

6 Science & Global Issues/Biology genetics Panel Member #1 I think that planting genetically modified crops to improve yield and reduce the need for insecticides will be good for our people and safe for the environment. Bt corn has raised corn yields in the United States. Investigations of Bt corn at a leading university showed that it did not harm monarch butterflies in the field. Bt corn seed might be more expensive, but it may also save farmers money and labor, since they will not need to purchase and spray the insecticides that fight the corn borer. Research has shown that farmers growing Bt corn use fewer chemical insecticides to fight other organisms that attack corn. In addition, one researcher found that Bt corn has lower levels of a fungal toxin that is common in corn. Because that toxin is harmful to children, Bt corn may be safer to eat than unmodified corn. Bt corn is just one example of how genetically modified organisms might contribute to the food supply. For example, genetically modified disease- and drought-resistant crops have already been developed. Researchers are also working to improve the nutritional quality of such basic foods as rice through genetic modification. By increasing food production in our country, we can help to end hunger and malnutrition among our people. We would no longer have to import corn, which is more expensive than growing it. We could also make money by selling our corn to other countries. Panel Member #2 I do not think we know enough about genetically modified crops for our country to invest in any of them at this time. Genetic engineering technology has not always resulted in improved crop yields. A study by the U.S.-based Union of Concerned Scientists found that Bt corn is the only genetically modified crop giving better yields, but the improvements were small. I m also concerned that it will harm monarch butterflies and other organisms, or cause other environmental damage. Many people think that changing just one or a few genes is unlikely to cause harm, because a single gene codes for just one protein. But I am concerned because one protein can have multiple effects in the organism. New discoveries in genetics suggest that the effects of inserting a gene from one organism into another organism s DNA are more complex than scientists once thought. Finally, the continual exposure of insects to insecticides nearly always leads to the development of resistant insect populations. With Bt in the corn itself, the insects are constantly exposed to the toxin, and are more likely to become resistant than when farmers spray it on their crops just a few times. For these reasons, I urge caution. We must feed our children today without harming the environment for the children of tomorrow. 266

7 A Genetically Modified Solution? Activity 1 Panel Member #3 Humans have been breeding crops to develop desirable traits for thousands of years. Genetic engineering technology is a faster and more precise way to make these changes. Genetic modification allows scientists to insert beneficial genes from one species into another, and that s not possible with breeding. Several genetically modified organisms have been used for more than 30 years to produce medicines. One example is the modification of Escherichia coli (E. coli) bacteria to produce the human hormone, insulin. Before this was produced in 1978, insulin was extracted from pig pancreases, which was time-consuming and more expensive to produce. With the hunger we face, it s time to allow the growth of genetically modified crops here. Corn is a major food for people and livestock. Research shows that Bt corn is most cost-effective in areas like ours, where crop losses to corn borers are large. People in our country are starving, and researchers have shown that Bt corn does improve yields. Research also shows that with Bt corn we do not have to rely as much on chemicals to control insects in the cornfields. I am certain that genetically modified crops will contribute to a sustainable food supply, help our farmers make a better living, and let our children think about schoolwork instead of their empty stomachs. Panel Member #4 I do not think genetically modified crops should ever be grown or eaten. The impact that they have on ecosystems and humans has not been fully explored. What if the plants breed with wild crops or other plants and spread the inserted genes? This has happened with some genetically modified crops. If it happened here it could be harmful for our native plants. Additionally, what impact will the proteins produced by the modified crops have on the health of humans or animals? There was a case of a soybean plant that was genetically modified to make it more nutritious by adding a gene for a Brazil-nut protein. A study published in the New England Journal of Medicine found that the nut protein produced by these soybeans caused allergic reactions in people allergic to Brazil nuts. As a result, the company that developed the modified soybean had to stop its work and not sell the soybeans. I am concerned that there might be other unintended consequences of planting such crops as Bt corn. Much more thorough scientific studies of each product are needed. These studies would divert resources from other approaches to sustainable agriculture, such as better soil management, relying on pests natural enemies, and other ecologically balanced approaches to pest control. 267

8 Science & Global Issues/Biology genetics Analysis 1. What is a genetically modified organism? 2. How might genetically modified food organisms affect each of the three pillars of sustainability: a. economic? b. social? c. environmental? 3. Did your initial ideas about Bt corn change? Explain your initial ideas. If they have changed, explain how and why. If they have not changed, explain why not. 4. Write a letter to the country s Office for Agriculture explaining your views on growing Bt corn. In your letter include a. a statement explaining your decision and the evidence and reasoning that led you to your conclusion. b. a description of the trade-offs of your decision. A trade-off is giving up something in order to gain something else. 5. Currently in the United States, federal law does not require foods containing genetically modified ingredients to be labeled as such. a. What would be the advantages of labeling foods that have genetically modified ingredients? b. What would be the disadvantages? c. Would you recommend labeling of foods that have genetically modified ingredients? Explain. Key vocabulary gene genetically modified organism genetic engineering trade-off 268