Genetically Modified Organisms

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1 Genetically Modified Organisms By Kendra Hogan For Dr. William R. Proulx, PhD, RD Associate Professor of Nutrition & Dietetics In partial fulfillment for the requirements of NUTR243 Food and Nutrition Education November 30, 2015

2 TABLE OF CONTENTS I. INTRODUCTION... 3 II. REVIEW OF LITERATURE.. 4 A. Increased Agricultural Productivity.. 4 B. Herbicide and Pesticide Use C. Nutritional Value III. CONCLUSIONS.. 8 IV. REFERENCES.. 9 2

3 INTRODUCTION The use of genetically modified organisms in crops has shown to create plants with desirable traits such as increased agricultural productivity at a lower cost, decreased use of pesticides, decreased use of herbicides, and the creation of foods with higher nutritional content (1). Malnutrition is a prevalent ailment that strikes millions of people. In many developing countries, malnutrition is the leading cause of death and in these countries the population is expected to at least double within the next 45 years. Without the use genetically modified products it would be nearly impossible to sustain nourishment for the world s expanding population. With the use of genetically modified genes, such as Bacillus thuringiensis genes in which are used widespread to kill harmful pests, crops are sustaining longer lives being able to withstand problems that are life threatening such as weather and pests. Research is still being done on both benefits and potential risks of genetically modified foods and crops. Environmental issues such as gene transfer, competition with natural species, and the disturbance of Darwinism are all potential risks that are being researched. This paper will present current research and studies in which indicate how biotechnology can affect the productivity, pesticidal and herbicidal use, and nutritional content as well as potential risks associated with this genetic modification. 3

4 REVIEW OF LITERATURE Increased Agricultural Productivity Huang et al. studied unique data from empirical micro-level study and field trials they conducted in China along with a modified GTAP models to determine the impact of biotechnology on China s production, trade, and welfare (2). A cotton variety with the Bacillus thuringienesis (Bt) gene to control the bollworm is one of the most oft-cited examples of the agricultural biotechnology process in China. This specific GM cotton was shown to contribute to 45% of China s cotton area and boosted the economy drastically. China has made very far progress with biotechnology. Ready for release and commercialization, China has also created rice resistant to insect pests and diseases, wheat resistant to the barley yellow dwarf virus, maize resistant to insects and with improved quality, soybeans resistant to herbicides, and transgenic potato resistant to bacterial disease. Along with these crop motifications, China has also progressed in plant and animal biotechnology for example nitrogen-fixing bacteria for rice and corn and transgenic pigs, respectively. China has the largest biotechnology plant outside of North America. The international debate has a large influence on the use of these GM foods and crops despite potential benefits to China and its economy. One of the most life-threatening issues to crops is weather; including droughts and frost. In a study by study by Shou et al. the expression of an enzyme in GM maize activates an oxidative signal cascade that confers cold, heat and salinity tolerance (3). This enzyme was found in a tobacco plant and was used in maize. Oxidative stress signaling has been shown to play a role in freezing tolerance. Activation through the expression of a mitogen-activated protein called kinase kinase kinase showed to provide benefits in transgenic tobacco at freezing 4

5 temperature bypassing cold acclimation. The study was done on a major cereal crop to determine if it could substantiate cold weather. Involvement of the mitogen-activated protein kinase cascade in oxidative stress signaling is conserved in eukaryotes therefore this test would be effective. Freezing tolerance was demonstrated to be enhanced in the expression of the Nicotiana PK1 gene in transgenic maize plants in which normally are sensitive to cold temperatures. The results of the study found that important plants could be genetically modified to be able to withstand these conditions. In her paper, Key et al. say that because primary cause of plant loss worldwide is abiotic stress, particularly salinity, drought, and temperature extremes, this is just one example of how agricultural productivity could be increased with the use of biotechnology (4). Herbicide and Pesticide Use Carvalho conducted a review of literature on the relationship between pesticide and herbicide use and its relationship with food safety (5). Studies were done in various areas of the world to find relationships between the pesticides and herbicides used there and any effects on human health. In tropical areas, where pests are more common, pesticides are used in massive amounts. Here, the residues of pesticides, especially the organochlorine and organophosphorous compounds are found in soils, the atmosphere and in the aquatic environment in relatively high concentrations. Studies performed on people living in rural areas of some countries, such as Costa Rica and Nicaragua, indicated direct exposure of many workers to the chemicals and acute poisoning with effects on reproduction and central nervous system. Bt seeds make the plant produce a toxin that kills major insect pests and Ht seeds make a plant live through the application of a pesticide that has the ability to kill every other plant on the field, such as weeds. 5

6 Bt varieties have incorporated the genes from a common bacteria known as Bacillus thuringiensis into various crop hybrids. Some Bt crops may even contain the genes of different bacterium. For example, in India Bt cotton in has genes to kill the cotton looper, red hairy caterpillar and the spiny bollworm. Bt cotton in the U.S. has genes to kill the cotton leaf perforator, the saltmarsh caterpillar, the cotton bollworm and six other insects common to North America instead of killing harmless pests and being released into the environment. There are less consequences seen with Bt seeds as compared to Ht seeds, however research still needs to be done on actual consequences to the environment and human health (6). Lehmann and Pengue did a study of herbicide tolerant soybeans in Argentina (7). Argentina produces 10% of the world s soybeans. In the 1990 s Argentina s soybean crops were given glyphosphate herbicide Roundup to keep them tolerant to pesticides. Transgenic Roundup ready soybeans went from covering approximately 800,000 hectares to 7 million hectares in just three years. Argentina can now produce soy at a lower cost due to lower herbicide costs, and lower equipment, fuel, and labor costs but the threat to competition with natural species could be a potential risk to consider. Nutritional Value Looking at the recombinant DNA technology use in a study done by Ye et al (8). we can see how biotechnology can contribute to the nutritional value of foods. The removal of the oilrich aleurone layer causes rice, a staple food for most countries, to lack several nutrients. Using a combination of transgenes, Ye et al enabled biosynthesis of provitamin A in the endosperm. Immature rice endosperm can produce uncolored carotene phytoene by expressing the enzyme 6

7 phytoene synthase due to being able to synthesize the early intermediate geranylgeranyl diphosphate. Synthesis of beta-carotene requires the complementation with three additional plant enzymes: phytoene desaturase and ζ-carotene desaturase (for two double bonds) and lycopene β-cycla. A bacterial carotene desaturase can be used because it is capable of introducing all four double bonds required. In the study, Agrobacterium-mediated transformation to introduce the entire β-carotene biosynthetic pathway into rice endosperm was used. The strategy of the Golden Rice Project was to introduce the correct metabolic steps into rice endosperm to allow β-carotene synthesis (3). Golden Rice is has been given to farmers in developing countries and aids with feeding countries and combating Vitamin A deficiency thus helping prevent blindness and death in which are prevalent consequences of this deficiency. 7

8 CONCLUSIONS Genetically modified crops have many potential benefits for food sustainability and food security. Crops that provide food and clothing for all humans and our doubling population are susceptible to conditions such as abiotic stress, drastic temperatures, and droughts. The prevention of these issues by making our crops strong enough to withstand them is done in various ways due to the translation of genes from various desirable sources such as other plants, animals, or bacterium. As seen with the activation of the expression of a mitogen-activated protein called kinase kinase kinase, this provided an important food source, maize, the ability to withstand freezing temperatures. These technologies keep crops alive and prevent the destruction of millions of crops. With technology such as glyphosphate herbicide Roundup and Bacillus thuringiensis (Bt) genes, naturally occurring herbicides and pesticides helps the environment by reducing the use of chemically created herbicides and pesticides. Now, instead of potentially harming other pests and insects genes are modified to target specific, harmful species. Having these desirable traits also lowers the cost of crops while increasing agricultural productivity greatly. Concerns with genetically modified organisms are very prevelant but there are many controversial studies. Environmental concerns are the greatest within this field, yet more research still needs to be done. 8

9 REFERENCES 1. Goldbas, A. (2014). GMOs: What Are They?...Genetically modified organisms. International Journal Of Childbirth Education, 29(3), p. 2. Huang, J., Hu, R., Van Meijl, H., & Van Tongeren, F. (2003). Biotechnology boosts to crop productivity in China: Trade and welfare implications. 3. Shou, H., Bordallo, P., Fan, J.-B., Yeakley, J. M., Bibikova, M., Sheen, J., & Wang, K. (2004). Expression of an active tobacco mitogen-activated protein kinase kinase kinase enhances freezing tolerance in transgenic maize. Proceedings of the National Academy of Sciences of the United States of America, 101(9), Key, S., Ma, J. K.-C., & Drake, P. M. (2008). Genetically modified plants and human health. Journal of the Royal Society of Medicine, 101(6), Calvalho, F. (n.d.). Agriculture, pesticides, food security, and food safety. In Environmental Science & Policy (Vol. 9, pp ). 6. Ganzel, B. (2009). GMOs & Pesticides. Retrieved from 7. Lehmann, V. and Pengue, W. A. (2000), "Herbicide tolerant soybean: Just another step in a technology treadmill?" Biotechnology and Development Monitor, No. 43, p Ye, X., Al-Babili, S., Kloti, A., Zhang, J., Lucca, P., Beyer, P., & Potrykus, I. (2000). Engineering the Provitamin A (-Carotene) Biosynthetic Pathway into (Carotenoid-Free) Rice Endosperm. Science,