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Genetically Modified Organisms. PG SBI 4U. What are Genetically Modified Organisms (GMOs)?. A GMO is any living things that has had its genome manipulated by humans, usually by inserting a gene from another species GMOs are very important for the food and medicine industries.
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Genetically Modified Organisms PG SBI 4U
What are Genetically Modified Organisms (GMOs)? • A GMO is any living things that has had its genome manipulated by humans, usually by inserting a gene from another species • GMOs are very important for the food and medicine industries. • Biotechnology is the science of genetic modification. • Also known as genetically engineered, recombinant or transgenic organisms. • In 2008, 13.3 million farmers in 25 countries were growing GMO crops on 1.25 million square kilometers
Selective Breeding • Humans have been manipulating the genomes of organisms for thousands of years • Humans have been using the process of selective breeding to choose the best plants and animals, and to gradually change the genomes of those species • Only the strongest, tastiest and most desirable individuals are allowed to breed and their genes are passed on to their offspring • These organisms not considered to be GMOs
Examples: • Wolves to Dogs: • Teosinte to Corn:
More Examples: • Brassicaoleracea or wild cabbage has been bred into cabbage, broccoli, cauliflower, brussels sprouts, kohlrabi and kale
Direct Genetic Modification • The insertion of foreign genes into organisms • Bacteria: • Plasmids are used as a vector to transfer foreign genes • A restriction enzyme is used to excise a specific gene which will anneal to a plasmid cut with the same enzyme • Bacteriophages are also commonly used to transfer DNA
DGM Plants • Some plants can be genetically modified by infecting them with a bacterium called Agrobacteriumtunefaciens • The desired gene is inserted into the “Ti” plasmid in the bacterium • When a plant is infected it incorporates some the plasmid DNA into its chromosome, so any of the plants offspring will carry those genes • An alternative method is the “Gene gun” • DNA attached to small gold or tungsten particles is fired at a piece of plant tissue
DGM Animals • Microinjection • the use of a micropipette to insert DNA into a cell • Uses needles 0.5-5μm in diameter • The foreign gene is inserted into the pronucleus of a fertilized egg cell • The genes of animals can also be modified using viruses because viruses naturally insert their DNA into animal cells
Recombinant Medicine • Bacteria can be made to produce important human proteins by inserting the human genes that code for these proteins into the bacterial genome • Examples: • Human insulin is now produced by E. coli bacteria for diabetics. In the past insulin from pigs or cattle was used and was much less effective • Human Growth Hormone (HGH) is also produced by recombinant bacteria. HGH was previously obtained from cadavers. • Others: Blood clotting Factors and Vaccines • Human proteins can also be produced in the body fluids of transgenic animals then refined
Genetically Modified Food • FlavrSavr Tomatoes • The first transgenic plants licensed to be eaten by humans • Golden Rice • Rice modified to contain β-carotene • Aimed to combat vitamin A deficiency (VAD) • VAD results in 2.5 million deaths of children under 5 and 250-500 thousand children going blind every year among other health problems • Insect and disease resistant crops • Soybeans, corn, canola, wheat, etc.
Other uses • GloFish • Zebrafish with a fluorescence gene taken from jellyfish are available as pets • Malaria-resistant mosquitoes • When introduced to the wild they would reproduce and spread the gene through the gene pool, decreasing the number of mosquitoes carrying malaria • “Enviropig”
Arguments Against GMOs • Environmental concerns • GMOs can mate with wild plants and create hybrids • GMOs and hybrids have a selective advantage and will outcompete wild plants • GMOs have unpredictable effects on other organisms (may be poisonous) • Loss of biodiversity • Human safety concerns: • Transgenic food may cause allergic reactions • People allergic to seafood may be allergic to plants with genes from fish • No labeling regulations • Social concerns • Market dominance in the food industry by a few companies
Arguments for GMOs • Medicines from GMOs are cheaper and of better quality than previous sources, saving lives • Plant GMOs with increased yield and insect/disease resistance provide more food with less land and reduce the need for poisonous pesticides and fertilizers • Food can be modified for increased nutrition • Ecological concerns of escaped GMOs becoming weeds apply equally to other domesticated plants as well as the effects of monocultures of soil health • GMO foods are tested for potential dangers before they are licensed for human consumption
Conclusion • Genetic engineering is an exciting field of science and new discoveries are made every day • There may be some dangers but all human inventions have an element of risk • GMOs have a huge potential to improve and save human lives
Sources • Knudsen, Guy R. "Impacts of agricultural GMOs on wildlands: a new frontier of biotech litigation." Natural Resources & Environment Summer 2011: 13+. Academic OneFile. Web. 3 Dec. 2011. • Hoyle, Brian, and K. Lee Lerner. "Genetically Modified Foods and Organisms." The Gale Encyclopedia of Science. Ed. K. Lee Lerner and Brenda Wilmoth Lerner. 3rd ed. Vol. 3. Detroit: Gale, 2004. 1772-1774. Gale Virtual Reference Library. Web. 3 Dec. 2011. • Watkins, Terry. "Transgenics." The Gale Encyclopedia of Science. Ed. K. Lee Lerner and Brenda Wilmoth Lerner. 3rd ed. Vol. 6. Detroit: Gale, 2004. 4071-4074. Gale Virtual Reference Library. Web. 3 Dec. 2011. • Di Giuseppe, M., Vavitsas, A., Ritter, B., Fraser, D., Arora, A., & Lisser, B. (2003). Biology 12. Toronto: Nelson. • Commonwealth Scientific and Industrial Research Organization. (2011). Biotechnology Online.Retrieved from http://www.biotechnologyonline.gov.au/ • Biotech Chronicles. Retrieved from http://www.accessexcellence.org/RC/AB/BC/ • (2003). Gene Guns. Retrieved from http://www.bio.davidson.edu/Courses/Molbio/MolStudents/spring2003/McDonald/Gene_gun.html • Pray, L. (2008) Recombinant DNA technology and transgenic animals. Nature Education.,1(1). Retrieved from http://www.nature.com/scitable/topicpage/recombinant-dna-technology-and-transgenic-animals-34513 • (2010). Glofish. Retrieved from http://www.glofish.com/ • Gallagher, J. (April 20, 2011). GM mosquitoes offer malaria hope. BBC News. Retrieved from http://www.bbc.co.uk/news/health-13128327 • (2011). DNA Microinjection Services. Retrieved from http://research.uci.edu/tmf/dnaMicro.htm • (2011). Golden Rice is part of the solution, Biofortified rice as a contribution to the alleviation of life-threatening micronutrient deficiencies in developing countries. http://www.goldenrice.org/ • (November 5, 2008). What are Genetically Modified (GM) Foods?. Retrieved from http://www.ornl.gov/sci/techresources/Human_Genome/elsi/gmfood.shtml • (2009). Cloning into a Plasmid. Retrieved from http://www.accessexcellence.org/RC/VL/GG/plasmid.php
Image Sources • Slide 4: http://visual.merriam-webster.com/animal-kingdom/carnivorous-mammals/dog-breeds_1.php, http://www.learner.org/courses/essential/life/images/show5.maize_teosinte.jpg • Slide 5: http://www.tainongseeds.com/Kohlrabi.html, http://bioweb.uwlax.edu/bio203/s2009/dymond_dani/Classification%20Information.htm, http://www.hort.purdue.edu/ext/senior/vegetabl/cabbage1.htm, http://groovyvegetarian.com/2007/11/10/10-fun-facts-about-broccoli/, http://www.bigoven.com/glossary/Cauliflower, http://www.lesliebeck.com/ingredient_index.php?featured_food=77, http://www.thatsfit.ca/2010/01/27/kale-chips-recipe-healthy-crunchy-homemade-snack/ • Slide 6: http://www.accessexcellence.org/RC/VL/GG/plasmid.php • Slide 7: http://www.bio.davidson.edu/Courses/Molbio/MolStudents/spring2003/McDonald/Gene_gun.html • Slide 8: http://images.tutorvista.com/content/biotechnology/micro-injection-process.jpeg, http://research.uci.edu/tmf/dnaMicro.htm • Slide 10: http://www.goldenrice.org/ • Slide 11:http://www.glofish.com/photos.asp