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Nuts and Bolts of GMOs - Harold Trick

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Harold Trick, Department of Plant Pathology, Kansas State University

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Nuts and Bolts of GMOs - Harold Trick

  1. 1. Nuts and Bolts GMOs Harold Trick Department of Plant Pathology Kansas State University Manhattan, KS HNT@ksu.edu Part I: The Science of GMOs Presentation to Women Managing the Farm Conference – Kansas 2/10/2017
  2. 2. Topics Addressed: • What are GMO or GE organisms? - (Definitions) • How are GMO (GE) crops made? • Why do we make them? • Are they safe? • How are they regulated? •What GE crops are on the market?
  3. 3. Percentage of Biotech Acreage in USA Source: Agricultural Statistics Board USDA-ERSFarmer benefits: herbicide and insect resistance
  4. 4. What Is a GE or (GMO)? • A genetically engineered organism is a living plant, animal, or microbe that incorporates laboratory- made recombinant DNA. • Same as “transgenic” • Less correctly referred to as “Genetically Modified Organism” or GMO Genetically Engineered Organism
  5. 5. • chemical substance of genes • assembly instructions for proteins • genetic code is part of each strand of the double helix • the instruction code is universal !!!! G--C A--T C--G A--T A--T T--A C--G C--G What is DNA?
  6. 6. What is a Gene? GenePromoter DNA RNA Protein Desired trait Terminator DNA Sequence tells the cell where and how of product to make
  7. 7. Recombinant DNA + = Cut and pasted artificially in the lab by molecular scissors Bacterial DNA Plant DNA Plant DNA with a small piece of bacterial DNA
  8. 8. Glow in the dark tobacco plant stem roots leaf
  9. 9. Pharmaceuticals Most if not all insulin on the market today is a GE product
  10. 10. Roundup Ready Soybeans Conventional Roundup Ready
  11. 11. Plant Transformation Lab and Field testing Breeding Program Public Release Gene Modification BASIC APPLIED Research Steps Gene Discovery
  12. 12. How to get the Gene into the plant ?
  13. 13. Inductio n CM4 Proliferatio n Development MSP Regeneration MSE Plant Recovery Starting Material Wheat Tissue culture Modified MS-based medium w/ 0.5 mg/L 2,4-D + 2.2 mg/L picloram 10-14 d post anthesis Modified MS-based medium w/ 0.2 mg/L 2,4-D Modified MS-based medium no hormones
  14. 14. Agrobacterium Particle gun Plant Transformation
  15. 15. The Gene Gun Plant tissue DNA
  16. 16. Particle Bombardment Nucleus Target Cell Metal particle DNA
  17. 17. Wheat embryo tissue transformed with DNA GFP: Green Fluorescent Protein Shows the EVENTS
  18. 18. Wheat shoot stably transformed with GFP
  19. 19. Regeneration of Plants
  20. 20. GMO Wheat Plant Ready to Test
  21. 21. TransgenicControl sprayed with 0.2% Liberty
  22. 22. Why Do We Do It? • To research gene function • To deepen the gene pool and gain access novel traits • To gain greater control of trait expression, including knocking out genes • To cheaply manufacture expensive or rare proteins (plantibodies, vaccines) • Food Security
  23. 23. Agricultural Biotechnology or Genetic Engineering can help increase our food supplies by providing protection against various stresses
  24. 24. • Limited starch deposition under high temperature • Soluble starch synthase (SSS)- heat liable Seed size/yield is sensitive to heat 65 °F 77 °F 95 ° Effects of temperature on seed size • Climate Models predict that Extreme Heat will occur every 1-3 years in the U.S • Every 2°F rise above 65°F results a ~3-6% loss in yield potential • Total 2015 US wheat production 2.1 billion bu. (USDA,NASS) • (wheat grown at 77°F results in 20-38% yield penalty)
  25. 25. 0 5 10 15 20 25 30 35 40 88 °F 91 °F 93 °F PercentYieldIncrease ComparedtoControlPlants Plant expressed ** ** ** * * * Validation: Plants expressing heat tolerant protein significantly outperforms controls Control non-transgenic Seeds harvested from 93 °F heat treatment Seed expressed trait Plant expressed trait
  26. 26. GM Traits: the benefits • Herbicide resistance • Insect resistance • Disease resistance • Pollen sterility • Salt, cold or drought tolerance • Altered ripening • Nutritional content • Allergen content • Altered oil content • Anti-oxidants Part II: Benefits and Risks of GMO's
  27. 27. Bt Sweet Corn • Conventional sweet corn sprayed multiple times with insecticides for corn earworms.
  28. 28. Transgenic Papaya Resistant to PRSV Papaya Ringspot Virus http://www.planthealthprogress.org/current/reviews/papaya/top.htm
  29. 29. Golden Rice: A Functional Food • Vitamin A deficiency causes blindness in some countries • Beta carotene (provitamin A) from daffodil
  30. 30. Risks of GMOs
  31. 31. Risk Analysis • Hazard identification • Hazard severity (worst case scenario) • Probability of hazard • Steps available to reduce risk • Risk balancing (risk/risk and risk/benefit trade-offs) • What is the acceptable risk level (margin of safety)
  32. 32. The public is bombarded with misinformation on GE crops
  33. 33. The public is bombarded with misinformation on GE crops - rat study retracted - control rats also had tumors 9/19/2012
  34. 34. Does GM plants cause autism?? http://www.organic-systems.org/journal/92/JOS_Volume-9_Number-2_Nov_2014-Swanson-et-al.pdf
  35. 35. What are the risk with Genetically engineered crops? • Environmental • Health National Academy of Science, World Health Organization and British Royal Society: Risks of GMOs are no different than conventional organisms
  36. 36. What are the Environmental Issues? • Loss of effectiveness of Bt pesticide due to over-use • Non-target effects • Escape of transgenes
  37. 37. Bt-toxin • Bacillus thuringiensis (or Bt)- Gram + soil bacterium that produces a protein toxin (cry) • Considered environmentally friendly – Effect specific classes of insects – No effect on mammals or honeybees • 1901- bacteria was discovered to have cause diseases in insects • 1920’s- the bacteria were used as insecticides • Currently used as an organic pesticide
  38. 38. Bt-toxin • Currently used as an organic pesticide • 1976 Bt gene was isolated • 1985 first plant engineered to express (tobacco) • 1995 Bt engineered potato approve by EPA • 1996 Bt corn, cotton, soybean and potatoes grown
  39. 39. Loss of effectiveness of Bt pesticide due to over-use Cotton: Bollworm Corn: corn borer corn earworm corn rootworm Soybean: bean looper soybean moth
  40. 40. Positive environmental impact 2001 North American Breeding Bird Survey: Populations of songbirds that frequent around cotton fields have increased significantly in the major U.S. cotton producing states, with increases of 20 percent in Arizona, over 30 percent in Mississippi and Alabama, and 10 percent in Texas. Quail nesting in cotton fields in south west, never before seen Environmental Protection Agency (EPA) (2010): “data provide a weight of evidence indicating no unreasonable adverse effects of Bt proteins expressed in plants to non-target wildlife”
  41. 41. Herbicide resistant plants allows farmers to use “no till” farming practices prevents erosion conserves water 2003- Adoption of GE plants resulted in a reduction of 443 million pounds of herbicides in USA
  42. 42. What are the Health Issues? • Eating “foreign” genes • Toxins • Nutritional content • Allergens • Medicines produced in plants proteins How can we ensure safety?
  43. 43. Biotech Regulatory Oversight In US -coordinated approach several agencies share responsibilities -each product is regulated on a case-by-case basis -government exercises oversight through a consultative process USDA-APHIS • Environmental EPA • Plant Pesticides FDA • Food •Livestock feed USDA-APHIS- Regulation of confined Trials NIH and Institutional Biosafety Guidelines Research & Development Confined field trials Food, Feed, & Safety Assessment 7-10yrs, minimum
  44. 44. USDA-APHIS • Environmental EPA • Plant Pesticides FDA • Food •Livestock feed USDA-APHIS- Regulation of confined Trials NIH and Institutional Biosafety Guidelines Research & Development Confined field trials Food, Feed, & Safety Assessment  
  45. 45. Environmental Risk Assessment Before a GE crop can be grown on a wide scale or sold commercially, its developers need to petition APHIS for “determination of non-regulated status” 1. Description of biology of non-modified plant 2. Relevant data and references 3. Complete a molecular characterization of GE plant 4. Detailed differences in genotypes between GE and Non-GE 5. Detailed differences in phenotypes between GE and Non-GE 6. Agricultural practices 7. Effects on non-target organisms 8. Indirect plant pest effects 9. Gene transfer potential between species which cannot interbreed Solicitation of public comments in the Federal Registar
  46. 46. Food and Feed Safety Assessment 1. Purpose of intended modification 2. Complete a molecular characterization of GE plant 3. Information on expressed proteins 4. Information on known or suspected allergenicity and toxicity 5. Information on compositional and nutritional characteritics 6. For foods known to be allergenic, any change in endogenous allergens 7. Comparisons of feeding studies comparing GM and non-GM Solicitation of public comments in the Federal Registar
  47. 47. Overall time to Commercialization 13.1 years from the initiation of the discovery of a trait to commercial launch of the transgenic plant in US Canola Corn Cotton Soybean All Crops Years 11.7 12.0 12.7 16.3 13.1 This overall time can be broken down to two overall stages: A. Research and development B. Registration and regulatory affairs R&D can further be broken down into subcategoriesSurvey by Phillips McDougall.2012
  48. 48. What is the Overall cost of bringing a GE event to the market? Activity Stage I. Early Discovery II. Late Discovery III. Construct Optimization IV. Commercial Event Production and Selection V. Introgression Breeding &Wide- Area Testing VI. Regulatory Science VII. Registration & Regulatory Between 2008 and 2012 overall cost was $136 million
  49. 49. http://www.simplotplantsciences.com (time.com)
  50. 50. Conclusions • Genetic engineering is a powerful tool to improve efficiency and nutrition of crops. • There are legitimate concerns about risks of GM crops that can be assessed. • NAS: “risks do not differ in kind” from conventional methods • GMOs are not inherently safe or unsafe • Products must be evaluated on a case- by-case basis
  51. 51. 2016 marked the 21th anniversary of biotech crops on the market • 181.5 million hectares (448 million acres) have been planted Worldwide • 18 million farmers in 28 countries plant biotech crops • Billions of people have consumed GE products (even you) • Cases of illness or deaths associated with GE products: 0

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