Genetically Modified Crops: Healthy Food or Frankenfood?ENGR 100wWhat is genetic engineering? Change DNA of a living organism Splice a gene from one organism to thechromosome of another Create “genetically modified organisms”(GMOs) or “transgenic organisms”Corn (resistance to corn borer)Cotton (built in resistance to insects)Tomatoes (Flavr Savr)SoybeansWorld malnutrition Insufficient calories(need 2200 Kcal/day) Single food diet Insufficient protein Insufficient vitamins Insufficient minerals ChildrendisproportionatelyaffectedSource: Cunningham & Cunningham, 2006Why genetic engineering? Improve yield (more production per acre) Resist drought, frost, pests, or disease Thrive in salty or low-nutrient soil Improve nutritional content Vitamins (vitamin A prevents blindness) Produce oils or plastics Produce vaccinesPest resistance Plants with genes for “endogenousinsecticides”Use Bacillus thuringiensis (Bt) – bacteriummakes toxins lethal to certain insectsBt gene transferred to corn, potatoes, cotton Farmers reduce insecticide spraying Bt-containing crops banned in EuropePotential problems Cross-breed with wild relativesCreate super-weedsReduce biodiversity Affect humans negativelyToxinsAllergies Create resistant varieties of pests Seeds costly – create uncompetitivemarketGMOs highly controversial ProponentsReduce hungerIncrease nutritional valueof foodsImprove standard of livingReduce application oftoxic chemicalsCreate naturally availablevaccines OpponentsBecome pests themselvesReduce biodiversityAccelerate pesticideresistance in insectsProduce toxic residue Insoils, water, or foodCreate economic barrierthat drives small farmersout of businessThe story of StarLink “StarLink” invented to resist a corn pest Only approved for animal feed Not approved for human because ofpotential allergic reaction 2001 StarLink found in consumer products(Taco Bell taco shells) $110 million class action law suit StarLink withdrawn from marketRoundup Ready crops (Monsanto) Resistant to treatment with RoundupRoundup is a herbicide (weed killer)Farmers can spray entire fields with Roundup, butGMO crops will survive Less tillage (called conservation tillage)Leaves more plant material in fields, which canreduce erosion and soil compactionGMOs grown worldwideThe five countries producing more than 95% of commercialized GMOOther countries producing commercialized GMO Only experimental cropsSource: http://urbngreen.com/?s=gmo12345U.S. – World leader in GMOsU.S Statistics - 2004 85% soybeans 76% cotton 45% corn 50% papayas 54% canola (rape seed)Number of acres worldwide planted with GM crops(source: (ISAAA) Global Review of Transgenic Crops 2003)Genetically modified animals(not yet approved for consumption) Atlantic salmonGrows twice as fast as native salmonGrowth hormone genes from oceanic pout CattleProduce milk with more calcium and certain proteinsthat improve processing PigsHigh in omega-3 fatty acids, which are essential tonormal growth in childrenNormally found in fishHave you eaten foods with GMOs Contained GM ingredients in 1999 but may ormay not now:Oreo cookiesCoca ColaHeinz KetchupMcDonalds’ hamburger bunsButterfingersJelly bellies It is really hard to find out which brands containGM ingredientsLabeling In United States labeling of GM food isvoluntary Mandatory labeling would require all USmanufacturers to test all food for GMCommon practice in EuropeCostly Potentially large impact on
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