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GMOs: What’s all the GMOs: What’s all the fuss?fuss?
Alan McHughenAlan McHughenUniversity of CaliforniaUniversity of California
Riverside, CA Riverside, CA [email protected]@ucr.edu
FPI SurveyFPI Survey
Are GM foods in US supermarkets?Are GM foods in US supermarkets? Do ordinary tomatoes contain genes?Do ordinary tomatoes contain genes? Would a tomato with a fish gene taste Would a tomato with a fish gene taste
“fishy”?“fishy”? If you ate a GM fruit, might it alter your If you ate a GM fruit, might it alter your
genes?genes? Can animal genes be inserted into a plant?Can animal genes be inserted into a plant? Give an example of GM food on the marketGive an example of GM food on the market
FPI Survey FPI Survey (% correct)(% correct)
Are GM foods in US supermarkets? Are GM foods in US supermarkets? 48%48% Do ordinary tomatoes contain genes? Do ordinary tomatoes contain genes? 40%40% Would a tomato with a fish gene taste “fishy”? Would a tomato with a fish gene taste “fishy”?
42%42% If you ate a GM fruit, might it alter your genes? If you ate a GM fruit, might it alter your genes?
45%45% Can animal genes be inserted into a plant? Can animal genes be inserted into a plant? 30%30% Give an example of GM food on the marketGive an example of GM food on the market
79% said GM tomatoes were on the market79% said GM tomatoes were on the market
What is What is GM/GE/Biotechnology ?GM/GE/Biotechnology ?
Any of several techniques used to add, Any of several techniques used to add, delete or amend genetic information delete or amend genetic information in a plant, animal or microbein a plant, animal or microbe
Used to make pharmaceuticals Used to make pharmaceuticals (insulin, dornase alpha, etc.), crops (insulin, dornase alpha, etc.), crops (Bt corn, disease resistant papaya, (Bt corn, disease resistant papaya, etc.) and industrial compounds etc.) and industrial compounds (specialty oils, etc.)(specialty oils, etc.)
History of genetic History of genetic engineeringengineering
rDNA began in 1973, with GE bacteriarDNA began in 1973, with GE bacteria First commercial product- insulin- in 1982First commercial product- insulin- in 1982 First food- cheese – 1988 (UK), 1990 (US)First food- cheese – 1988 (UK), 1990 (US) First food crop, FlavrSavr™ tomatoes, in First food crop, FlavrSavr™ tomatoes, in
19941994 So far, there have been no documented So far, there have been no documented
cases of harm from GMOs.cases of harm from GMOs.
Who uses Biotech Who uses Biotech products ?products ?
Consumers: diabetics, victims of CF, Consumers: diabetics, victims of CF, cancer, etc.cancer, etc.
Farmers in US/Canada (2004): Farmers in US/Canada (2004): Soybean: 85% of acreageSoybean: 85% of acreage Cotton: 75% of acreageCotton: 75% of acreage Corn: 45% of acreage (15% HT+ Corn: 45% of acreage (15% HT+
30% IR)30% IR) Canola: 77% of acreage.Canola: 77% of acreage.
Economics of GE crops Economics of GE crops
In the USA, six GE crops— soybeans, corn, In the USA, six GE crops— soybeans, corn, cotton, papaya, squash and canola — cotton, papaya, squash and canola — provide:provide:
Over 5 Over 5 billion billion additional pounds of food additional pounds of food and and fiber on the same acreage,fiber on the same acreage,
improved farm income by $1.9 improved farm income by $1.9 billion,billion, andand
reduced pesticide use by 46 reduced pesticide use by 46 millionmillion pounds.pounds.
National Center for Food and Agricultural Policy (NCFAP), National Center for Food and Agricultural Policy (NCFAP), 20042004
Documented benefits of Documented benefits of biotech cropsbiotech crops
FarmersFarmers Increased yields (especially in Increased yields (especially in
developing countries)developing countries) Decreased chemical input costsDecreased chemical input costs Cleaner fields, less dockageCleaner fields, less dockage Less fuel usedLess fuel used Less tillageLess tillage Fewer adverse health effects (esp. Fewer adverse health effects (esp.
China).China).
Documented benefits of Documented benefits of biotech cropsbiotech crops
ConsumersConsumers Safer food (less mycotoxin in maize, esp Safer food (less mycotoxin in maize, esp
Africa/Asia)Africa/Asia) Safer food (greater regulatory scrutiny)Safer food (greater regulatory scrutiny) Less pesticideLess pesticide Environmental benefits.Environmental benefits.
Documented benefits of Documented benefits of biotech cropsbiotech crops
EnvironmentEnvironment Less pesticide burdenLess pesticide burden Safer pesticidesSafer pesticides Improved soil from less tillageImproved soil from less tillage Less fuel usageLess fuel usage Increased biodiversityIncreased biodiversity
Sources: NCFAP, Plant Biotechnology, June 2002; Sources: NCFAP, Plant Biotechnology, June 2002; November 2004November 2004
Canola Council of Canada, An agronomic and economic Canola Council of Canada, An agronomic and economic assessment of transgenic canola, 2001assessment of transgenic canola, 2001
Munkvold, G.P., Hellmich, R.L., and Rice, L.G. 1999. Munkvold, G.P., Hellmich, R.L., and Rice, L.G. 1999. Comparison of fumonisin concentrations in kernels of Comparison of fumonisin concentrations in kernels of transgenic Bt maize hybrids and non-transgenic hybrids. transgenic Bt maize hybrids and non-transgenic hybrids. Plant Dis. 83:130-138.Plant Dis. 83:130-138.
So, What’s the fuss?So, What’s the fuss?
GE is unnatural, ‘crossing the species GE is unnatural, ‘crossing the species barrier’barrier’
GE food contains bacterial genesGE food contains bacterial genes GE plants spread uncontrollablyGE plants spread uncontrollably GE is unethicalGE is unethical GE is ‘risky’GE is ‘risky’ GE is controlled by corporate interestsGE is controlled by corporate interests GE crops are unregulated; no prior GE crops are unregulated; no prior
scrutinyscrutiny
Much of the fuss comes Much of the fuss comes from:from:
FearmongeringFearmongering MisunderstandingMisunderstanding
ScienceScience Conventional food systemsConventional food systems
Covert Political agendaCovert Political agenda Philosophical/ideological perspectivesPhilosophical/ideological perspectives
‘‘Natural’ movement; organics; lacks Natural’ movement; organics; lacks context.context.
Concerns with GMOsConcerns with GMOs
Scientific Scientific EnvironmentEnvironment Health safetyHealth safety
Non-scientificNon-scientific EthicalEthical Socio-economicSocio-economic PoliticalPolitical
Covert TradeCovert Trade Covert Covert
TechnologicalTechnological
Crops: traditional and Crops: traditional and modernmodern
All new crops (traditional or All new crops (traditional or biotech) must be genetically biotech) must be genetically altered and distinctaltered and distinct
DUS= DUS= DDistinct, istinct, UUniform, niform, SStable.table.
Variety release Variety release requirements: requirements:
genetically engineered genetically engineered cropscrops
USDA (APHIS) - environmental USDA (APHIS) - environmental issuesissues
HHS (FDA)- food and feed safetyHHS (FDA)- food and feed safety
EPA- pesticide usage issues.EPA- pesticide usage issues.
DUS, plus…DUS, plus… Molecular characterization of inserted Molecular characterization of inserted
DNA, DNA, Southern and restriction analysesSouthern and restriction analyses PCR for several fragments, PCR for several fragments, Various enzyme assays (ALS, NOS, Various enzyme assays (ALS, NOS,
NPT-II)NPT-II) Copy number of insertsCopy number of inserts Size of each fragment,Size of each fragment, Source of each fragmentSource of each fragment Utility of each fragmentUtility of each fragment How fragments were recombinedHow fragments were recombined How construct was delivered into flaxHow construct was delivered into flax Biological activity of inserted DNA Biological activity of inserted DNA
(genes)(genes) Quantitative analyses of novel proteins Quantitative analyses of novel proteins
(western analyses)(western analyses) Temporal activity of inserted genes Temporal activity of inserted genes spatial activity of inserted genesspatial activity of inserted genes complete amino acid analysiscomplete amino acid analysis detailed amino acid analysis for valine, detailed amino acid analysis for valine,
leucine and isoleucine leucine and isoleucine Toxicity (feeding trials were not Toxicity (feeding trials were not
warranted)warranted) Allergenicity (feeding trials were not Allergenicity (feeding trials were not
warranted)warranted) Biological analysis:Biological analysis:
Pathogenicity to other organismsPathogenicity to other organisms dormancy, dormancy, outcrossingoutcrossing potential for horizontal gene transferpotential for horizontal gene transfer seed productionseed production flowering time, flowering time, flower morphologyflower morphology analysis of relativesanalysis of relatives stability of inserted genes over seed stability of inserted genes over seed
generationsgenerations survivability in natural environmentsurvivability in natural environment survivability in agricultural survivability in agricultural
environment in presence of herbicideenvironment in presence of herbicide survivability in agricultural survivability in agricultural
environment in absence of herbicideenvironment in absence of herbicide Interaction with other organisms- Interaction with other organisms-
alterations to traditional relationshipsalterations to traditional relationships Interactions with other organisms- Interactions with other organisms-
novel speciesnovel species Changes to persistence or Changes to persistence or
invasivenessinvasiveness Any selective advantage to the GMOAny selective advantage to the GMO Any selective advantage to sexually Any selective advantage to sexually
compatible speciescompatible species Plan for containment and eradication Plan for containment and eradication
in the event of escape in the event of escape
Methods of Genetic Methods of Genetic ModificationModification
Recombinant DNA (rDNA)Recombinant DNA (rDNA)--------------------------------------------------------------------------
MutagenesisMutagenesis Somaclonal variationSomaclonal variation Embryo rescueEmbryo rescue Crossing or selection within a Crossing or selection within a
populationpopulation IntroductionIntroduction Succession/invasion.Succession/invasion.
Similar products, similar Similar products, similar risks ?risks ?
HT Canola:HT Canola: GroupGroup Sulfonylurea Sulfonylurea 2. ALS/AHAS inhibitor2. ALS/AHAS inhibitor Trifluralin Trifluralin 3. Mitotic inhibitor3. Mitotic inhibitor Bromoxynil Bromoxynil 4. PGR4. PGR Triazine Triazine 5. Photosynthetic inhibitor5. Photosynthetic inhibitor Glyphosate Glyphosate 9. EPSP Synthase inhibitor9. EPSP Synthase inhibitor Glufosinate Glufosinate 10. Glutamine Synth. 10. Glutamine Synth.
InhibitorInhibitor
Different process, same Different process, same productproduct
Rice: disease resistance (Rice: disease resistance (Xa21Xa21 gene) gene) Canola: herbicide tolerance (SuRs)Canola: herbicide tolerance (SuRs)
Coffee: reduced caffeineCoffee: reduced caffeine Maize: enhanced tryptophanMaize: enhanced tryptophan Flaxseed: reduced linolenic acidFlaxseed: reduced linolenic acid Soybean: increased oleic acid.Soybean: increased oleic acid.
Changes in Genetically Modified Changes in Genetically Modified Food:Food:
DNADNA content: content: highly variable, depends on specieshighly variable, depends on species
GM additional DNA, GM additional DNA, approx. 1 gene added to 25,000 genes. approx. 1 gene added to 25,000 genes.
Or, approx. 0.000 000 7% new DNA. Or, approx. 0.000 000 7% new DNA. Protein:Protein:
highly variable, depends on food. highly variable, depends on food. GM protein, approx. 0.00004 % of GM protein, approx. 0.00004 % of
total protein is novel.total protein is novel.
1 kilo of Wheat (grain) 1 kilo of Wheat (grain) contains:contains:
StarchStarch 680g680g ProteinProtein 160160 WaterWater 100100 OilOil 20 20 Fiber/ashFiber/ash 40 40 Other: StonesOther: Stones 2 2 GlassGlass Weed SeedsWeed Seeds RatshitRatshit ArsenicArsenic 10μg10μg DNADNA trace.trace.
Crossing of existing approved plant varieties*
*includes all methods of breeding
Conventional pollen based crossing of closely related species
Selection from a heterogenous population
rDNA via Agrobacterium , transfer of genes from closely related species
Mutation breeding, chemical mutagenesis, ionizing radiation
Somatic hybridization
Somaclonal variation (SCV)
rDNA biolistic, transfer of genes from closely related species
rDNA biolistic, transfer of genes from distantly related species
Conventional pollen based crossing of distantly related species or embryo rescue
Selection from a homogenous population
rDNA via Agrobacterium , transfer of genes from distantly related species
Likelihood of unintended effects (arbitrary scale)Less likely More likely
Newly ModifiedOrganism
[A]
Is the compositionunintentionally changed?
Have nutrient levels changed?[B]
Is additional compositional evaluation warranted?
[D]
Can one identifycompounds for
targeted analysis?[C]
No FurtherEvaluation
[G]
Biologically Significant Levels ofCompound
Are new or enhanced levels of apotentially hazardous compound
present, and/or are levels of beneficialcompounds reduced?
[E]Post-MarketSurveillance
[F]
UNKNOWN
Is additional health evaluationwarranted?
[H]
UNKNOWNYES OR
UNKNOWN
Complex Mixture Studies[I]
YES
YES
NO
YES
NO
NO
YES
NO
NAS/IOM ConclusionsNAS/IOM Conclusions
Foods with a novel substance or Foods with a novel substance or altered levels of usual components altered levels of usual components should be scrutinized for safety, should be scrutinized for safety, regardless of method of breedingregardless of method of breeding
A new modified food, whether GE or A new modified food, whether GE or other, whose composition is similar to other, whose composition is similar to conventional version may warrant conventional version may warrant little or no safety evaluation.little or no safety evaluation.
More findingsMore findings
There are NO documented adverse There are NO documented adverse health effects from eating GE foods.health effects from eating GE foods. Allegations of harm are unfoundedAllegations of harm are unfounded
Genetic engineering is NOT inherently Genetic engineering is NOT inherently hazardoushazardous
GE should NOT be the trigger for GE should NOT be the trigger for regulatory assessmentregulatory assessment
Regulation on the basis of method of Regulation on the basis of method of breeding is scientifically unjustified.breeding is scientifically unjustified.
Consensus of scientific Consensus of scientific societiessocieties
The method of breeding is The method of breeding is immaterial to the risk of hazard. All immaterial to the risk of hazard. All breeding involves changes to DNA breeding involves changes to DNA and carries some (albeit small) riskand carries some (albeit small) risk
There is no scientific justification to There is no scientific justification to single out GE for ‘special’ regulatory single out GE for ‘special’ regulatory or liability considerations.or liability considerations.
• Number of field trials of GMOs > 10,000
• Number of countries growing GM crops 17** home to > half the world’s population
• Global acreage (2004) 200M
• Number of GM plant species tested 41
• Number of significant adverse incidents 0
Significant Numbers (from OECD and ISAAA databases)
ConclusionConclusion
When you encounter concerns with When you encounter concerns with GMOs:GMOs: Is it science or non-science?Is it science or non-science?
Science is product orientedScience is product oriented Science is evidence basedScience is evidence based
If science, demand peer reviewed evidenceIf science, demand peer reviewed evidence If peer reviewed data, ask how it compares to If peer reviewed data, ask how it compares to
Status QuoStatus Quo Some GMOs are beneficial, others detrimentalSome GMOs are beneficial, others detrimental
NOTHING IS RISK FREE!NOTHING IS RISK FREE!
Documented benefits of Documented benefits of biotech cropsbiotech crops
FarmersFarmers Increased yields (especially in Increased yields (especially in
developing countries)developing countries) Decreased chemical input costsDecreased chemical input costs Cleaner fields, less dockageCleaner fields, less dockage Less fuel usedLess fuel used Less tillageLess tillage Fewer adverse health effects (esp. Fewer adverse health effects (esp.
China).China).