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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.
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Geneticengineering 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. A strawberry resistant to frost + = Arctic fish DNA strawberry
What are genetically modified organisms? Common GM foods • Vegetables • Tomatoes • Potatoes • Rice • Cheese • Meat • 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
Modifying Genes Also called recombinant DNA technology, molecular cloning, and genetic engineering. • Restriction enzymes are used to “cut” DNA segments from one genome. • DNA ligases are used to “paste” them into another genome. Foreign DNA
How are animals targeted? • The microinjection method uses a fine needle to inject a solution of DNA into a developing embryo. 6
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. 7
Pest resistance Herbicide resistance Cold tolerance Drought tolerance Cheaper food Reducing world hunger and improving world health Improved farming More food Increased nutrition Edible vaccines Potential Benefits Humanitarian: Environmental: reduced use of herbicides and chemicals in farming.
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 resources • Development of drought resistant crops • Development 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 yields • Higher stress tolerance • Longer shelf-life • New products and growing techniques
The Bad • Health • Potential human health impacts • Allergens and toxins • Transfer of antibiotic resistance markers • Adversely changing the nutrient content of a crop • Unknown long term effects
The Bad • Environment • Unintended transfer of transgenes through cross-pollination • Herbicide tolerance passed to other plants • Creation of superweeds • Cross pollination of GM weeds with similar wild species
The Bad • Environment • Loss of flora and fauna biodiversityl • GM plants outcompete natural plants • Unintended harm to wildlife, beneficial insects and soil microbes • Insect resistance to pesticides • EXAMPLE: 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 • LabelingNot mandatory in United States or Canada • New advances may be skewed to the interests of rich countries. • Creation of biological weapons.
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 thuringiensisthat 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.