What are Genetically Modified Organisms (GMOs)?

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Transcript What are Genetically Modified Organisms (GMOs)?

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SBI 4U
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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
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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
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Wolves to Dogs:
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Teosinte to Corn:
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Brassica oleracea or wild cabbage has been
bred into cabbage, broccoli, cauliflower,
brussels sprouts, kohlrabi and kale
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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
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Some plants can be genetically modified by
infecting them with a bacterium called
Agrobacterium tunefaciens
◦ 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
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An alternative method is the “Gene gun”
◦ DNA attached to small gold or tungsten particles is
fired at a piece of plant tissue
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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
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The genes of animals can also be modified
using viruses because viruses naturally insert
their DNA into animal cells
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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
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Flavr Savr Tomatoes
◦ The first transgenic plants licensed to be eaten by
humans
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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
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Insect and disease resistant crops
◦ Soybeans, corn, canola, wheat, etc.
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GloFish
◦ Zebrafish with a fluorescence
gene taken from jellyfish are
available as pets
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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
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“Enviropig”
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Environmental concerns
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Human safety 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
◦ Transgenic food may cause allergic reactions
 People allergic to seafood may be allergic to plants with
genes from fish
◦ No labeling regulations
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Social concerns
◦ Market dominance in the food industry by a few
companies
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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
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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
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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-transgenicanimals-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 lifethreatening 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
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Slide 4: http://visual.merriam-webster.com/animal-kingdom/carnivorous-mammals/dogbreeds_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
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Slide 10: http://www.goldenrice.org/
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Slide 11: http://www.glofish.com/photos.asp