Task. - Opposing position evidence - Evidence that refutes opposing evidence - Reasoning that justifies why opposing position is unacceptable.

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1 Genetically Modified Foods Reading and Writing Assignment Task In the last few years, there has been a lot of media attention in China, in the United States, in Europe and also other countries, to the topic of genetically modified (GM) crops. Since we have recently discussed genetically modified organisms in class, this activity will ask you to consider this as a real world issue. First, to become an expert on GM crops, choose two or three (minimum) of the attached articles to read and learn about the advantages and disadvantages of genetically modified crops. Once you have become an expert, you must take a position on GM crops with logical and scientific argument to support your position. You will present your argument in the form of a letter to a local congress person in the US (think of a place where you may attend college or live in for a period of time in the US) who will be voting on a bill soon that will allow the use of GM crops in our area. When writing this letter, your stance on GM crops must be clear and supported by at least two pieces of evidence with appropriate reasoning to justify why each piece of evidence supports your position. Additionally, in your letter you should give one strong piece of evidence that supports the opposing positions on GM crops with a piece of evidence that refutes the opposing positions as well as logical reasoning that justifies why the opposing position is unacceptable. Consider this outline when writing your letter (and use the rubric provided to help you exceed the standard of this assignment): - Your position on GM crops (are you for or against the use of GM crops) C - Evidence 1 from article - Rationale for how evidence 1 supports your position - Evidence 2 from article - Rationale for how evidence 2 supports your position - Opposing position evidence - Evidence that refutes opposing evidence - Reasoning that justifies why opposing position is unacceptable. A letter to the congress/government is preferred but is not the only choice for you. As I ve mentioned in the message, you can also write to your beloved parents/your awesome me or Ms B/Mr Xigui Li/the canteen/mr Yongyuan Cui/Mr Zhouzi Fang/or anyone you d like to write to. But make sure you follow the other requirements.

2 Article 1 Pros and Cons of Genetic Engineering and- cons- of- genetic- engineering.html By Manali Oak December 15, 2011 While genetic engineering can lead to the introduction of greater quality traits in organisms, it can also have undesirable side effects. To understand the pros and cons of genetic engineering, read on The science of indirectly manipulating an organism's genes using the techniques like molecular cloning and transformation to alter the structure and nature of genes is called genetic engineering. Genetic engineering can bring about a great amount of transformations in the characteristics of an organism by the manipulation of DNA, which is like the code inscribed in every cell determining how it functions. Like any other science, genetic engineering also has pros and cons. Let us look at some of them. Pros of Genetic Engineering Crops like potato, tomato, soybean and rice are currently being genetically engineered to obtain new strains with better nutritional qualities and increased yield. The genetically engineered crops are expected to have a capacity to grow on lands that are presently not suitable for cultivation. The manipulation of the genes in crops is expected to improve their nutritional value as also their rate of growth. Biotechnology, the science of genetically engineering foods, can be used to impart a better taste to certain foods. Engineered seeds are resistant to pests and can survive in a relatively harsh climatic conditions. The recently identified plant gene known as At- DBF2, when inserted in tomato and tobacco cells is seen to increase their endurance to harsh soil and climatic conditions. Biotechnology can be used to slow down the process of food spoilage. It can thus result in fruits and vegetables having a greater shelf life. Genetic engineering in food can be used to produce totally new substances such as proteins and other food nutrients. The genetic modification of foods can be used to increase their medicinal value, thus making available homegrown edible vaccines. Genetic engineering has a great potential of succeeding in case of human beings. This specialized branch of genetic engineering, which is known as human genetic engineering is the science of modifying the genotypes of human beings before birth. The process can be used to manipulate certain traits in an individual. Positive genetic engineering deals with enhancing the positive traits in an individual like increasing longevity or human capacity while negative genetic engineering deals with the suppression of the negative traits in human beings like certain genetic diseases. Genetic engineering can be used to obtain a permanent cure for certain dreaded diseases. If the genes responsible for the exceptional qualities in some individuals can be discovered, these genes can be artificially introduced into genotypes of other human beings. Genetic engineering in human beings can be used to change the DNA of individuals to bring about desirable structural and functional changes in them.

3 Cons of Genetic Engineering Genetic engineering in food involves the contamination of genes in crops. Genetically engineered crops may supersede the natural weeds; they may prove harmful for the natural plants. Undesirable genetic mutations can lead to allergies in crops. Critics believe that genetic engineering in foodstuffs can rather hamper the nutritional value while enhancing their taste and appearance. Horizontal gene transfer can give rise to new pathogens. While increasing the immunity to diseases in plants, the resistance genes may get transferred to the harmful pathogens. Gene therapy in human beings can manifest certain side effects. While treating one defect, the therapy may lead to another. As one cell is responsible for many characteristics, the isolation of the cells responsible for a single trait is indeed difficult. Genetic engineering can hamper the diversity in human beings. Cloning can be detrimental to individuality. Moreover, such processes may not be affordable for the masses, thus making gene therapy, an impossibility for the common man. Genetic engineering may work wonders but it is after all a process of manipulating the nature. It is altering something that is not an original human creation. Modifying something that one has not created is always challenging.

4 Article 2 Genetic Engineering- Part 2: Pros and cons of genetically engineering crops Rakesh S. Chandran, Ph.D. IPM Specialist WVU Extension Service This article was published in the February 2001 issue of West Virginia Farm Bureau News. Genetically modified crops have generated much public interest and controversy. A New York Times article (Dec. 15, 2000) indicated that the scientific information available today is not adequate to draw conclusive deductions on the crops' potential benefits or risks to the environment. The article was based on a review of refereed journal articles published in Science (December 2000). Genetically modified crops (transgenic crops) are best known for their abilities to resist pests (weeds, insects, and diseases) or for produce containing high nutrient levels. Transgenic crops capable of manufacturing vaccines and other pharmaceuticals are also in the pipeline. Some of the well- known transgenic crops on the market today are Roundup Ready Soybean, Roundup Ready com, Bt Corn, IMI corn, etc. In the previous article (Farm Bureau News; vol. 8, no. 11), I discussed the basic principles of genetic engineering. Now that we have the background information, let's examine some of the pros and cons of the technology in agriculture. Allergies. Eating certain transgenic foods has occasionally led to the development of allergies. A study reported in the New England Journal of Medicine in 1998 showed that people consuming transgenic soybean intended as animal feed developed certain allergic reactions. Transgenic crops marketed for human consumption have not been linked directly to causing widespread allergies. Monarch butterfly mortality. Recent studies reported in Science and Oecologia journals suggested that pollen from the transgenic Bt com may be fatal to monarch butterflies, which feed on milkweed coated with com pollen. Scientists have confirmed the mortality of monarch butterflies exposed to Bt com pollen under both laboratory and field conditions. Proponents of the technology claim that under field conditions the concentration of pollen on milkweed may not reach levels that cause lethal effects. Scientists from Iowa State University are examining this more closely, and their findings should be published soon. A study published in Nature (1999) indicated that secretions from remains of Bt com adversely affected certain other soilborne nontarget insect species. Soil Erosion. Herbicide- tolerant crops are used for post- emergent weed control in no- till farming. This reduces the need for tillage, which in turn reduces soil erosion and nutrient losses. A potential environmental risk comes with this technique because it involves total vegetation control, which may affect an ecosystem's species diversity. Herbicide- resistant weeds. The evolution of "superweeds" capable of resisting herbicides as a result of using herbicide- tolerant crops has been a topic of public interest. Such a phenomenon is highly unlikely because there are more than 12 distinct groups of herbicides displaying different sites and modes of action (Herbicide Handbook, Weed Science Society of America). The popular herbicide, Roundup, is only one

5 member of one of these herbicide groups. Therefore, the likelihood of a weed becoming resistant to all known herbicides is almost impossible. The same argument and counter- argument are true for "escapes" of transgenic plants into the surrounding habitat. Food Supply and Pesticide Usage. Transgenic crops may provide increased profits to the farmer while providing cheaper and more nutritious food. Genetic engineering also has helped make crops available that could not otherwise tolerate adverse environmental conditions (drought, cold, high salt levels in the soils, etc.). Such crops are capable of resisting pests, generating higher yields, and producing food with high nutrient content. They are considered an effective means of dealing with pest problems while reducing production costs. Opponents of the technology argue that transgenic crops would increase our dependence on pesticides. This may be true in some instances but not in others. For example, Bt com reduces the need for insecticides since this transgenic corn can produce toxins to kill the European com borer pest, which otherwise would require insecticide applications. Indirect benefits of reduced insect damage include lower levels of fungal toxins associated with insect- damaged com. Gene flow. The flow of transgenes into other organisms through pollution (termed "genetic pollution") may pose unknown risks to the ecosystem. Once these genes are released, it is difficult to recall them. Proponents of the technology claim that this form of gene pollution is similar to introducing alien species into an ecosystem. The ecosystem is dynamic, and human interference caused it to change throughout history. Some organisms have become a nuisance although they were originally introduced as a biological control agent (e.g., Japanese ladybug). Crop diversity. Because genetic engineering focuses on crops with certain highly desirable traits, genetic diversity within the crop could be diminished. This can make crops more susceptible to natural calamities such as disease outbreaks. Such problems also have been encountered with hybrids generated by traditional breeding techniques. Faster breeding. A possible benefit of transgenic crops or animals is that they can be bred for desirable traits very precisely and much faster than when traditional methods are used. The related disadvantage is that because the actual "breeding" in genetic engineering is carried out under laboratory or sterile conditions, the implications under field conditions may not be fully understood until a problem arises. Nutrient levels. Certain transgenic crops (e.g., "golden rice" capable of synthesizing the precursor of Vitamin A) are capable of producing higher amounts of nutrients and vitamins, which could be have a great impact on solving nutrition problems in heavily populated and underdeveloped countries. Resistant microbes. Although there is no evidence, there are claims that transgenic crops may lead to the release of resistant strains of microbes into the environment by plants. This has been contradicted by proponents of the technology who state that such risks are highly unlikely compared to similar releases from medical or veterinary practices. Pharmaceuticals. Researchers are testing transgenic plants that are valuable to farmers and consumers now. They are capable of producing vaccines, pharmaceuticals, and other materials used in the medical industry. But their ability to safely contain such products has been questioned.

6 Disease pathogens. Plant pathogens capable of causing cancers (Agrobacterium tumefaciens) are used sometimes to carry the novel genes into the transgenic plants. There is a low likelihood that such pathogens could recombine with their equivalents in the plant and cause new plant diseases. Other techniques (e.g., "gene gun") can be used to insert genes into the DNA of an organism, which may rule out the possibility of such recombining. Several more arguments for and against the use of this technology are found in the media today. Most of them are subjective and speculative. The topic is a very complex one, the ramifications of which may involve many disciplines. Therefore, future research may provide answers to some of the uncertainties we face now.

7 Article 3 Genetically modified crops (GMCs): pros and cons Chris Dubey Hartford Biology Examiner July 5, modified- crops- gmcs- pros- and- cons How GMCs affect you Genetically modified crops (GMCs), also known as transgenic crops, raise some important ethical and practical issues. If you ve ever debated whether GMCs are good or bad, or if you re still sitting on the fence, then you could use a review of the benefits and risks of GMCs. However, before delving into the pros and cons, one might wonder, How do GMCs affect me? The answer is at least threefold: (1) If you re a U.S. resident, you might be interested to know that the United States grows much of the world s transgenic crops. In 2007, the U.S.A. grew 54 percent of the world s GMCs, making the United States the producer of the majority of transgenic crops. (2) Many common foods in the U.S. contain GMCs, even if that fact isn t advertised. Presently, the federal government does not require that GMCs be labeled as genetically modified. GMCs approved for sale in the United States include canola, chicory, corn, papaya, potato, rice, soy, squash, sugar beet, and tomato. However, transgenic corn, papaya, and soy are the three most distributed GMCs in the U.S. If you ve eaten corn bread, corn meal, tortilla chips, popcorn, French fries, potato chips, soymilk, or even veggie burgers, then there s a good chance that you ve consumed GM food products. (3) If you re a Connecticut resident, you might be interested to know that, in Connecticut, 40 percent of organic handlers and 40 percent of manufacturers and processors of agricultural products do not test to ensure that foods that reputedly are not genetically modified actually are non- GM. According to a 2007 survey by the United States Department of Agriculture, Economic Research Service, only 60% of organic handlers of agricultural products in Connecticut and only 60% of manufacturers and processors always test to verify whether foods claimed to be free of genetically modified organisms (GMOs) actually are free of GMOs. Yet scare tactics overlook the irrefutable benefits of GMCs. Pros of GMCs Many GMCs are genetically engineered with pest resistance. For example, Bt varieties are transgenic cultivars containing a foreign gene that causes the crops to produce Bt endotoxin, a natural insecticide, lethal to such pests as the European corn borer. The endotoxin is derived from the soil bacterium Bacillus thuringiensis. Because Bt crops produce their own insecticide, the use of these crops lowers the need to use chemical insecticides, which might be harmful to the environment or to human health, in addition to being costly to farmers.

8 GMCs can also be engineered to possess herbicide tolerance. The most efficient herbicides also kill crops, but crops such as soy, cotton, and corn can be made tolerant to the herbicide glyphosate. Glyphosate, the active ingredient in the weedkiller Roundup, is an herbicide that is effective in low doses, nontoxic to humans, and rapidly decayed by microbiota. Using the bacterium Agrobacterium tumifaciens as a vector for the gene that grants glyphosate resistance, scientists can create plants able to grow in environments containing a concentration of glyphosate 4 times higher than necessary to kill the wild type plant. Other adaptations can be imbrued into GMCs, such as virus resistance and drought resistance. The agricultural supply company Monsanto Company, which sells Roundup and operates a site in Mystic, Connecticut, manufactures GM seeds with insect protection, herbicide tolerance, weather protection, and increased productivity. Additionally, GMCs can be made with relatively nonadaptive traits that are, nonetheless, beneficial to humans. GMCs can be made more nutritious and given a propensity for higher yields than their non- GM equivalents. Thus, GMCs can increase the nutrition of the public, while increasing the profits of farmers. One example is golden rice, a cultivar of transgenic rice that contains extra beta- carotene, which the human body converts to vitamin A. For another example, in an article in Scientific American, agricultural economists Terri Raney and Pirabhu Pingali describe studies of farmers who cultivated GMCs in developing nations. The research showed that the farmers had increased crop yields and spent less on pesticides. Although the GM seeds were more expensive than the non- GM seeds, the farmers profits from the genetically modified crops was more than the farmers lost as a result of the higher prices of the transgenic seeds. Raney and Pingali also report that Bt rice engendered better pest control and higher yields in China, GM soy increased productivity by an average of 10% in Argentina, and GM cotton decreased pesticide burns and sickness in the Makhathini Flats of the KwaZulu- Natal province in Africa. Cons of GMCs So, you might wonder, if genetically modified crops can be made hardier, more nutritious, and easier to care for, then what s the basis to the argument against GMCs? Well a lot. Research validates the environmental risks of GMCs. GM crops can disseminate their foreign genes into the environment, such as by interbreeding with non- GM plants. One study reveals gene flow from GM creeping bentgrass, up to a distance of 21 kilometers from the bentgrass. Furthermore, GM crops that produce their own pesticides could create tougher pests. This could happen because the pesticides that the crops produce could kill off most susceptible pests, leaving a large population of resistant organisms to survive and reproduce more pests that are resistant. To prevent this, the Environmental Protection Agency requires that farmers grow an area of non- GM crops next to Bt crops. Yet some farmers report being too tired to fulfill this requirement. Moreover, the pesticides that some GMCs produce can spread through the food web and possibly disrupt natural ecological relationships. In a study published in 2005 in Molecular Ecology, James D. Harwood et al. of the University of Kentucky found that, probably through bioaccumulation and biomagnification, Bt

9 endotoxin concentrates in nontarget arthropods, such as spiders, ladybugs, and damsel bugs. This could affect the survival rate of important predators of insect pests. In another study, it was demonstrated that Bt corn produced pollen toxic to caterpillars of the monarch butterfly, a favorite of wildlife watchers. Scientific evidence also supports the health risks of genetically engineered crops to humans. For instance, if a crop that s allergenic is functioning as a genetic donor to a GMC, then the GMC can also cause allergic reactions. In one example, GM soy acquired the allergen 2S albumin from Brazil nut. Thus, the soy caused allergic reactions like the Brazil nut from which it acquired its genetic material. What s more, some GM crops can cause an allergic reaction even if that allergic reaction would not be caused by their genetic donors. In one study, published in 2005 in the Journal of Agricultural and Food Chemistry, GM peas were bioengineered with a foreign gene from a nonallergenic bean. Although the bean source of the foreign gene was nonallergenic to the mice in the study, the GM peas caused allergic reactions in the mice. Debate continues over whether some genetically modified crops are toxic to humans. A controversial study published in 2009 by Joël Spiroux de Vendômois et al. in the International Journal of Biological Sciences concluded that three cultivars of Monsanto s GM corn caused signs of toxicity in the liver and kidneys of rats. Monsanto gave a lengthy response, disputing the study. Finally, GM crops are often more expensive than their non- GM equivalents. Monsanto has patented its Bt cottonseed in Argentina, which allowed the company to sell the Bt cottonseed at a higher price than non- GM cottonseed. As a result, few Argentine farmers have made use of the Bt cotton.

10 Article 4 Predators delay pest resistance to Bt crops Date: March 4, 2014 Source: Cornell University via Science Daily Crops genetically modified with the bacterium Bt (Bacillus thuringiensis) produce proteins that kill pest insects. Steady exposure has prompted concern that pests will develop resistance to these proteins, making Bt plants ineffective. Cornell research shows that the combination of natural enemies, such as ladybeetles, with Bt crops delays a pest s ability to evolve resistance to these insecticidal proteins. This is the first demonstrated example of a predator being able to delay the evolution of resistance in an insect pest to a Bt crop, said Anthony Shelton, a professor of entomology at Cornell University's New York State Agricultural Experiment Station in Geneva, N.Y., and a co- author of the paper. Xiaoxia Liu, a visiting scientist from China Agricultural University who worked in the Shelton lab, is the lead author on the paper published in the journal PLoS One. Bt is a soil bacterium that produces proteins that are toxic to some species of caterpillars and beetles when they are ingested, but have been proven safe to humans and many natural enemies, including predaceous ladybirds. Bt genes have been engineered into a variety of crops to control insect pests. Since farmers began planting Bt crops in 1996 with 70 million hectares planted in the United States in 2012, there have been only three clear- cut cases in agriculture of resistance in caterpillars, and one in a beetle. Resistance to Bt crops is surprisingly uncommon, said Shelton. To delay or prevent insect pests from evolving resistance to Bt crops, the U.S. Environmental Protection Agency promotes the use of multiple Bt genes in plants and the practice of growing refuges of non- Bt plants that serve as a reservoir for insects with Bt susceptible genes. Our paper argues there is another factor involved: the conservation of natural enemies of the pest species, said Shelton. These predators can reduce the number of potentially resistant individuals in a pest population and delay evolution of resistance to Bt. In the study, the researchers set up large cages in a greenhouse. Each cage contained Bt broccoli and refuges of non- Bt broccoli. They studied populations of diamondback moth (Plutella xylostella) larvae, a pest of broccoli, and their natural enemies, ladybird beetles (Coleomegilla maculata), for six generations. Cages contained different combinations of treatments with and without predators, and with and without sprayed insecticides on the non- Bt refuge plants. Farmers commonly spray insecticides on refuge plants to prevent loss by pests, but such sprays can kill predators and prey indiscriminately.

11 The results showed that diamondback moth populations were reduced in the treatment containing ladybird beetles and unsprayed non- Bt refuge plants. Also, resistance to Bt plants evolved significantly slower in this treatment. In contrast, Bt plants with no refuge were completely defoliated in treatments without ladybirds after only four to five generations, showing rapid development of resistance in the pests. In the treatment with sprayed non- Bt refuge plants and predators, diamondback moth populations were reduced, but the larvae more quickly evolved resistance to the Bt plants. These results demonstrate the effectiveness of Bt plants in controlling the pest population, the lack of effect of Bt on the predators and the role predators play in delaying resistance to Bt plants in the pest population, said Shelton. Story Source: The above story is based on materials provided by Cornell University. The original article was written by Krishna Ramanujan. Note: Materials may be edited for content and length.

12 Article 5 Manipulating heat, drought tolerance in cowpeas Date: February 27, 2014 Source: Texas AgriLife Research via Science Daily Cowpeas, known as black- eyed peas in the U.S., are an important and versatile food legume grown in more than 80 countries. Texas A&M University scientists are working to map the genes controlling drought and heat tolerance in recent varieties. New and improved varieties of cowpeas have numerous adaptive traits of agronomic importance, such as day maturity, drought tolerance, heat tolerance, aphid resistance and low phosphorus tolerance, said Dr. Meiping Zhang, Texas A&M AgriLife Research associate research scientist in College Station. Under a National Institute for Food and Agriculture grant of $500,000, Zhang and other Texas A&M scientists will take advantage of the recently developed DNA sequencing technology to map and ultimately clone the genes controlling drought and heat tolerance for molecular studies and deployment of these genes in other crops, she said. Joining Zhang on the project are Dr. Hongbin Zhang, Texas A&M professor of plant genomics and systems biology and director of the Laboratory for Plant Genomics and Molecular Genetics; Dr. B.B. Singh, a visiting scholar and cowpea breeder with the Texas A&M soil and crop sciences department; and Dr. Dirk Hays, Texas A&M associate professor of physiological and molecular genetics, all in College Station. The goal of the study is to develop single nucleotide polymorphisms or SNP markers, the latest DNA marker technology, enabling efficient manipulation of heat and drought tolerances in cowpeas and related species, Zhang said. Cowpeas were chosen for the study because they are a high protein grain, vegetable, fodder and high nitrogen- fixing legume that can be intercropped with corn, cotton and other crops in many countries, including the U.S., Zhang said. "We know it is highly tolerant to drought, heat and several other biotic and abiotic stresses," she said. "This research will use high- throughput site- associated DNA sequencing to map the genes controlling drought and heat tolerance and to develop SNP markers, enabling efficient manipulation of heat and drought tolerances in cowpea and related species." Zhang said they have already developed a mapping population of 110 recombinant inbred lines from a cross of two cowpea lines that are highly tolerant or susceptible to both drought and high temperature. This population is being augmented into more than 200 recombinant inbred lines for the new project.

13 "We will not only map drought and heat tolerant genes, but also develop a platform for mapping genes controlling several other biotic and abiotic stress tolerances such as aphid resistance and low phosphorus tolerance, both of which are also of extreme significance for agricultural production of many crops." The drought and heat tolerant genes, once defined and cloned, will significantly advance understanding of the molecular basis underlying plant tolerances to these stresses, Zhang said. This will help researchers design tools to effectively combine multiple traits into new cultivars adapted to the globally changing climate in this and related crops, thus supporting the long- term genetic improvement and sustainability of U.S. agriculture and food systems, she said. Story Source: The above story is based on materials provided by Texas AgriLife Research. Note: Materials may be edited for content and length.

14 Article 6 'Superweeds' linked to rising herbicide use in GM crops, study finds Date: October 2, 2012 Source: Washington State University A study published this week by Washington State University research professor Charles Benbrook finds that the use of herbicides in the production of three genetically modified herbicide- tolerant crops - - cotton, soybeans and corn - - has actually increased. This counterintuitive finding is based on an exhaustive analysis of publicly available data from the U.S. Department of Agriculture's National Agriculture Statistics Service. Benbrook's analysis is the first peer- reviewed, published estimate of the impacts of genetically engineered (GE) herbicide- resistant (HT) crops on pesticide use. In the study, which appeared in the open- access, peer- reviewed journal Environmental Sciences Europe, Benbrook writes that the emergence and spread of glyphosate- resistant weeds is strongly correlated with the upward trajectory in herbicide use. Marketed as Roundup and other trade names, glyphosate is a broad- spectrum systemic herbicide used to kill weeds. Approximately 95 percent of soybean and cotton acres, and more than 85 percent of corn, are planted to varieties genetically modified to be herbicide resistant. "Resistant weeds have become a major problem for many farmers reliant on GE crops, and they are now driving up the volume of herbicide needed each year by about 25 percent," Benbrook said. The annual increase in the herbicides required to deal with tougher- to- control weeds on cropland planted to GE cultivars has grown from 1.5 million pounds in 1999 to about 90 million pounds in Herbicide- tolerant crops worked extremely well in the first few years of use, Benbrook's analysis shows, but over- reliance may have led to shifts in weed communities and the spread of resistant weeds that force farmers to increase herbicide application rates (especially glyphosate), spray more often and add new herbicides that work through an alternate mode of action into their spray programs. Story Source: The above story is based on materials provided by Washington State University. The original article was written by Brian Clark. Note: Materials may be edited for content and length.