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Genetic engineering. The science and debate over genetically modified food. What are genetically modified organisms?. TRANSGENIC ORGANISMS Involves the insertion of DNA from one organism into another OR modification of an organism’s DNA in order to achieve a desired trait. - PowerPoint PPT Presentation
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The science and debate over genetically modified food
GENETIC ENGINEERING
WHAT ARE GENETICALLY MODIFIED ORGANISMS?
• TRANSGENIC ORGANISMS
• Involves the insertion of DNA from one organism into another OR modification of an organism’s DNA in order to achieve a desired trait.
+ A strawberry resistant to frost
=Arctic fish DNA strawberry
• Foods that contain an added gene sequence
• Foods that have a deleted gene sequence
• Animal products from animals fed GM feed
• Products produced by GM organisms
Common GM foods Vegetables Tomatoes Potatoes Rice Cheese Meat
WHAT ARE GENETICALLY MODIFIED ORGANISMS?
Also called recombinant DNA technology, molecular cloning, and genetic engineering.1. Restriction enzymes are used to “cut” DNA
segments from one genome.2. DNA ligases are used to “paste” them into
another genome.Foreign DNA
MODIFYING GENES
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HOW ARE ANIMALS TARGETED?
• The microinjection method uses a fine needle to inject a solution of DNA into a developing embryo.
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HOW ARE PLANTS TARGETED?
• Agrobacterium that normally infects plants with disease is used to infect plants with genes of interests or…
• A particle gun is used to shoot small bits of metal coated with the gene into the plant.
Humanitarian:
Improved farming
Cheaper food
More food
Increased nutrition
Reducing world hunger and improving world health
Pest resistance
Herbicide resistance
Cold tolerance
Drought tolerance
Edible vaccines
Environmental: reduced use of herbicides and chemicals in farming.
POTENTIAL BENEFITS
THE GOOD• Society • Increased food security
for growing populations• Lower cost of food • Increase in the amount
of successful crops that yield more money
• Help stomp out famine
THE GOOD Increased Production
Development of crops that can be grown in marginal soil
Reduced strain on nonrenewable resourcesDevelopment of drought
resistant cropsDevelopment of salt-tolerant
crops Development of crops that
make more efficient use of nitrogen and other nutrients
THE GOOD
Reduced use of pesticides and herbicides►Development of pest
resistant crops ►Reduced herbicide use is
better for the environment and reduces costs for farmers
THE GOOD
Improved crop quality Development of frost resistant
crops Development of disease
resistant crops Development of flood resistant
crops
Improved nutritional quality Development of foods designed to
meet specific nutritional goals
THE GOOD
Enhanced taste and quality
Reduced maturation time
Higher yieldsHigher stress tolerance Longer shelf-lifeNew products and
growing techniques
THE BAD Health
Potential human health impactsAllergens and toxinsTransfer of antibiotic
resistance markersAdversely changing the
nutrient content of a cropUnknown long term effects
THE BAD Environment
Unintended transfer of transgenes through cross-pollination
Herbicide tolerance passed to other plantsCreation of
superweedsCross pollination of
GM weeds with similar wild species
THE BAD Environment
Loss of flora and fauna biodiversitylGM plants outcompete
natural plantsUnintended harm to wildlife,
beneficial insects and soil microbes
Insect resistance to pesticidesEXAMPLE: Herbicide
resistant GM Oilseed Rape crossed with similar plant species and gave them herbicide tolerance.
THE UGLY• Domination of world food
production by a few companies • Increasing dependence on
industrialized nations by developing countries
• Biopiracy, or foreign exploitation of natural resources
• Labeling Not mandatory in United States or Canada
• New advances may be skewed to the interests of rich countries.
• Creation of biological weapons.
HOW COMMON ARE GMO FOODS?
WHY DO IT?
• Rice is not high in essential nutrients
• Modifications• + daffodil genes and a
bacterium = beta-carotene content significantly increased
• + genes from a french bean = double the iron content.
WHY DO IT?
• Tomatoes- Introduce genes to increase shelf life.
• Potato - modified to produce a beetle killing toxin
• Yellow squash –In the USA two GM-squash (zucchini) species are approved for cultivation and as foodstuff. These have two or three envelop protein genes as protection against virus attack.
WHY DO IT?
• Canola – modified to resist one type of herbicide or pesticide
• Bt corn – corn that contains a chemical normally found in the soil bacterium Bacillus thuringiensis that is toxic to insects but not to humans
GM CANOLACANADIAN-AUSTRALIAN RELATIONS• Bayer Crop Science produces genetically modified canola
in Australia for the Canadian market.
• It is produced to resist the herbicide “Liberty” and can yield up to 20% higher than conventional canola.
ROUNDUP READY
• Genetically engineered to withstand the herbicide glyphosate, the active ingredient of Monsanto’s‘ herbicide Roundup.
• They are also known as "glyphosate tolerant crops." RR crops deregulated in the U.S. include: corn, soybeans, canola, cotton, sugarbeets, and alfalfa.
YOU CHOOSE