2 Before Reading Any Further… What is the first impression you get when you hear “genetically modified” foods?
3 Is it…12? orWhat’s scarier is not knowing the facts!
4 What is DNA? DNA is molecule of life. 3DNA is molecule of life.It contains all of instructions (genes) required to make an organism.
5 What are genetically modified foods? Also called genetically modified organisms (GMO).Involves the insertion of DNA from one organism into another OR modification of an organism’s DNA in order to achieve a desired trait.45+A strawberry resistant to frost=Arctic fish DNAstrawberry
6 Examples of GMO’sGolden rice – rice that contains beta-carotene (Vitamin A), which is not found in regular rice.Bt corn – corn that contains a chemical normally found in a bacterium (Bacillus thuringiensis) that is toxic to insects but not to humans.Herbicide resistant plants.
7 Modifying GenesAlso 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
8 How are animals targeted? The microinjection method uses a fine needle to inject a solution of DNA into a developing embryo.6
9 How are plants targeted? Agrobacterium that normally normally infects plants with disease is used to infect plant with gene of interests or…A particle gun is used to shoot small bits of metal coated with the gene into the plant.7
10 How common are GM foods?48 foods have been approved for use by the Canadian Food Inspection Agency.ProductsCornCanolaPotatoesTomatoesSquashSoybeansFlaxCottonseed oilSugarbeetsDerived ProductsCorn syrupTofuCanned foodsSoya sauceAnimals that feed on GMOs…….AND MOREDetails can be found at:
11 How common are GMO foods? 8Labeling of GM foods is not mandatory unless if there is a health or safety concern (Health Canada/Canadian Food Inspection Agency)
12 Potential Benefits Humanitarian: Improved farmingCheaper foodMore foodIncreased nutritionReducing world hunger and improving world healthPest resistanceHerbicide resistanceCold toleranceDrought toleranceEdible vaccinesEnvironmental: reduced use of herbicides and chemicals in farming.
13 Potential Environmental Hazards 11Reduced effectiveness of pesticides as insects become resistant to engineered toxins.Loss of biodiversityHarm to other organismsPollen from Bt corn was shown to cause high mortality rates in monarch butterfly larvae(9). BUT follow-up studies have shown that the exposure levels in the fields are negligible(10).
14 Potential Environmental Hazards Gene Transfer to non-target speciesHerbicide resistant plants and weeds could cross breed and create “superweeds”To address this one could:Create sterile male plants that don’t produce pollenEngineer the plants so that pollen doesn’t contain the foreign genesCreate buffer zones of non-GM crops around GM crops. The buffer crops would not be harvested.
15 Potential Human Health Risks AllergensGenetic engineering could potential introduce or create allergensFor example, inserting genes from a nut into another plant could be dangerous for people who are allergic to nutsUnknown health risksBiological processes involve a lot of INTERACTIONSIt is often difficult to identify every possible interaction.
16 Economic Hazards Elimination of competition Suicide seeds GM seeds are patentedSuicide seedsPlants with sterile seeds that are infertile are createdFarmers are forced to buy seeds every yearHowever, some companies have reduced costs or donated GM seeds to impoverished nations.
17 Creating a balance So are GM foods a good or bad thing? It depend on each individual case.Consumers, the government and scientists should be responsible for weighing the benefits against the costs.Improved NutritionResistance to diseaseReduced use of chemicalsEnvironmental risksHealth risksEconomic risks
18 Sources www.enn.com www.propanefl.com/ images/corn.jpg opg/images/dna.jpgGJOA/haven.htmlFruitber.htmlwww2.utmb.edu/scccb/mouse/ images/microinjection.jpgss.jircas.affrc.go.jp/engpage/ jarq/32-4/hagio/fig4.htmTransgenic pollen harms monarch larvae (Nature, Vol 399, No 6733, p 214, May 1999)GM corn poses little threat to monarch (Nature Biotechnology, Vol 17, p 1154, Dec 1999)monarch.html