GENETICALLY MODIFIED FOODS. Maria Teresa Paramio. UAB.

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1 GENETICALLY MODIFIED FOODS. Maria Teresa Paramio. UAB.

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4 DEFINITION Genetically modified (GM) foods are foods derived from organisms whose genetic material (DNA) has been modified in a way that does not occur naturally, e.g. through the introduction of a gene from a different organism. Currently available GM foods stem mostly from plants, but in the future foods derived from GM microorganisms or GM animals are likely to be introduced on the market. Most existing genetically modified crops have been developed to improve yield, through the introduction of resistance to plant diseases or of increased tolerance of herbicides.

5 GENETICALY MODIFIED FOODS VEGETALES ANIMALES MICROORGANISMOS Currently available GM foods stem mostly from plants, but in the future foods derived from GM microorganisms or GM animals are likely to be introduced on the market. Most existing genetically modified crops have been developed to improve yield, through the introduction of resistance to plant diseases or of increased tolerance of herbicides.

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7 qué son los genes?

8 HOW MANY GENES ARE?

9 GM CROPS BENEFITS 1. HIGHER PRODUCTIVITY: PEST RESISTENCE AND HERBICIDE TOLERANCE 2. MORE NUTRITIOUS AND TASTIER FOODS. 3. DISEASE AND DROUGHT-RESISTANT PLANTS 4. FOOD WITH LONGER SELF LIFE 5. FASTER GROWING PLANTS 6. MEDICAL FOODS USED AS VACCINES OR OTHER MEDICAMENTS.

10 THE GOLDEN RICE 1. RICE RICH IN VITAMINE A 2. ADDITION OF 3 NEW GENES. 3. LACK OF VITAMINE A AFFECTS MILLIONS OF CHILDREN IN THE WORLD

11 CROPS TRANSGENIC METHODOLOGIES: CELL MODIFICATIONS Gene-Gun: to transfer DNA is particle bombardment (gene gun) where small gold particles coated with DNA molecules are bombarded into the cell. Infection with Agrobacterium tumefaciens. The most commonly used gene transfer tool for plants is a circular molecule of DNA (plasmid) from the naturally occurring soil bacterium,

12 CROPS TRANSGENIC METHODOLOGIES: MODIFIED CELL SELECTION The principal methodologies to select the gen modified plants are: 1. marker genes that confer antibiotic or herbicide resistance are used to favor growth of the transformed cells relative to the non-transformed cells. For this method, genes responsible for resistance are inserted into the vector and transferred along with the gene(s) conferring desired traits to the plant cells. When the cells are exposed to the antibiotic or herbicide, only the transformed cells (containing and expressing the selectable marker gene) will survive. The transformed cells are then regenerated to form whole plants using tissue culture methods. 2. Fluorescence genes. 3. Marker genes of temperature, salinity, minerals, etc found in the cell culture medium.

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14 CROPS TRANSGENIC METHODOLOGIES:REGENERATION OF MODIFIED PLANTS

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19 POTENTIAL RISKS OF GM FOOD 1. ENVIROMENTAL HAZARS 2. HUMAN HEALTH RISKS 3. ECONOMIC CONCERNS

20 ENVIROMENTAL HAZARS Modified plants or animals may have genetic changes that are unexpected and harmful. Modified organisms may interbreed with natural organisms and out-compete them, leading to extinction of the original organism or to other unpredictable environmental effects. Plants may be less resistant to some pests and more susceptible to others. Unintended harm to other organisms Biodiversity lost

21 HUMAN HEALTH RISKS Allergencity Unknown effects of human health Antibiotic resistance Higher level of toxics in food.

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23 ECONOMIC CONCERNS Poor countries and farmers will not be able to afford seeds for GM crops, thus widening the gap between the wealthy and the poor. Because the GM seeds are infertile farmers would need to buy a fresh supply of seeds each year. GE crops are in the hands of very few companies. Monsanto most notoriously, along with Dupont, Syngenta, BASF, Bayer and Dow, dominate GE research and patents, corner 60% of the world seed market, and control 76% of the world agrichemical market.

24 CONCERNS ABOUT GM AGRICULTURE 1. MORE UNIFORME AND SUSCEPTIBLE AGRICULTURE 2. LO W AGRICULTURAL BIODIVERSITY 3. HIGHER ENERGY NEEDS

25 TRANSGENIC ANIMALS 1. FASTER GROWING ANIMALS 2. PHARMING: peoducers of human pharmaceutical proteins 3. XENOTRANSPLANTATIONS

26 Transgenics to improve animal production Biological function Expected advantages Resistance to diseases Digestion and metabolism Milk composition Wool growth Carcass growth Reproduction Lower use of antibiotics / Higher welfare Simpler breeding / Higher production Lower infection risk for humans Lower pollution / Higher production Deep metabolic change Adaptation to available feed / Better feed use Reduced allergenicity and intolerance Optimized protein and/or lipid composition Protection against disease (active and passive immunization) Enhanced nutriceutical content Enhanced growth and optimized wool compostion. Higher muscle development Lower lipid storage and better lipid composition Higher prolificity

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28 METODOS DE TRANSGÉNESIS EN ANIMALES 1. Gene pronuclear injection 2. Spermatozoa as gen vectors 3. Virus as gen vectors 4. Nuclear Cells Transfer

29 Transgenic fish Extracopies of Growth Hormone gene. Animales transgénicos Tomado de: Devlin et al., Nature, 2001.

30 AQUABOUNTY