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Transcript of Informing the public about modern biotechnology and biosafety Sixth Dubai international Food safety...
Informing the public about modern biotechnology and biosafety
Sixth Dubai international Food safety Conference Session
“Moving with the trends and developments in food safety."
Dubai, 28 February 2011
Piet van der Meer,
Horizons sprl, Belgium HORIZONS sprl
Topics
Frequently asked questions:
What is genetic modification/engineering? How is it different from conventional breeding?
What are the potential benefits of GM crops?
How is safety of GM crops addressed ?
What are the experiences with GM crops to date?
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Since humans started farming about 10,000 years ago, farmers have used crossing and selection to improve crops so that they:
- produce more
- taste better
- are stronger in the field
- have a longer ‘shelf life’
- etc
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Conventional breeding
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For 1000s of years, breeding was largely ‘trial and error’
19th century: Gregor Mendeldiscovered the rules of cross breeding.
Early 20th century: discovery of inducing mutations by radiation and chemicals.
Early 20th century: discovery of hybrids
Crop breeding has made major achievements and is crucially important for food security
Conventional breeding
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Teosinthe
Today’s sugar maize
Conventional breeding
Breeding and induced mutation also have some limitations: 1. Cross breeding only works between related plants.
2. For some species breeding is extremely difficult.
3. Breeding can take very long, e.g. apples.
4. “Linkage drag” – not only the desired genes go across.
5. Induced mutation is undirected and unpredictable.
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Conventional breeding
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Scientific discoveries in the 20th century to overcomethese limitations:
Discovery of DNA and ‘genes’ located on chromosomes
Discovery of special enzymes to ‘cut and paste’ genes,restriction enzymes, ligases, etc.
Discovery of transfer of genes into plant cells
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Genetic Modification of Plants
Genetic Modification of Plants
Traditionalplant breeding
x
“elite”variety
Related variety
GeneticModification
any gene
sourceHORIZONS sprl
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Genetic Modification of Plants
Technical characteristics of GM compared with breeding:
• Highly specific
• Faster
• Possible with plants that do not cross sexually
• Much greater reservoir of genes
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Genetic Modification
New technology:
• Is it useful?
• Is it safe?
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Biotechnology - the broader context
Escalating global challenges:
Growing world population (9 billion in 2050) Increased consumption of food, feed, and fiber Increasing demand for renewable fuels Loss of agricultural land Shortage of water for irrigation. Climate change Reduced agrobiodiversity Environmental degradation Loss of natural habitats and biodiversity
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Biotechnology - the broader context
Escalating global challenges:
Growing world population (9 billion in 2050) Increased consumption of food, feed, and fiber Increasing demand for renewable fuels Loss of agricultural land Shortage of water for irrigation. Climate change Reduced agrobiodiversity Environmental degradation Loss of natural habitats and biodiversity
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• The world will not be able to feed itself without destroying the planet unless a fundamental transformation of agricultural production takes place.
• Farmers have to produce more while having less impact on the environment.
• Need for “Sustainable intensification” (FAO)
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Genetic engineering - the broader context
Farmers need the availability of crop plants that:
- produce more per hectare,
- produce more per litre of water,
- are less dependent on pesticides and fertilisers,
- can grow on marginal land,
- have enhanced nutritional value
- have reduced post harvest losses,
- reduce soil erosion,
- etc.
Genetic engineering - the broader context
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Genetic engineering - the broader context
These immense challenges cannot be solved by conventional techniques alone.
Modern biotechnology can contribute significantly to finding solutions for these challenges (Earth Summit – Agenda 21, 1992; World Summit 2005)
The future of the agriculture is not a matter of “either this or that technology” but rather of combining the most suitable approaches of each available technology.
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Situation with GM crops to date
• Since the early 80s, a massive biotechnology research effort is conducted in many research institutions all over the world to improve crop plants.
• In Agenda 21 (1992) a detailed blueprint was agreed for international collaboration in biotechnology research
• Many thousands of research trials with GM plants, trees, and micro-organisms have been conducted over the last decades.
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Situation with GM crops to date
• Since 1996, GM crops have been grown commercially by farmers over more than 1 billion hectares world wide.
• In 2010, 15.4 million farmers planted 148 million hectares of biotech crops in 29 countries
• The GM crops grown commercially today are mainly soybean, cotton, maize and canola with insect resistance and/or herbicide tolerance.
Source: www.isaaa.org. HORIZONS sprl
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Genetic Modification
New technology:
• Is it useful?
• Is it safe?
- for the environment- as food and feed
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Biosafety - History
1972: First publication recombinant DNA
1974: ‘Berg Letter’: hopes and concerns - moratorium
1975: Asilomar: end of moratorium - safety case by case
1986: first transgenic plants
1986: OECD rDNA safety recommendations - “Blue Book”
1986: US coordinated framework for regulation
1986: European Directives on GMOs HORIZONS sprl
Biosafety – History
1992: UNCED, Rio De Janeiro 1992: Agenda 21
- maximise benefits - minimise risks
1992: Convention on Biological Diversity
- art 19: international collaboration on biotechnology
- art 8g: national biosafety systems
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Biosafety - History
2000: The Cartagena Protocol on Biosafety.
• Procedures for transboundary movement of living modified organisms in absence of national regulations
• Agreed principles and methodology for risk assessment
• Mechanism for information sharing - Biosafety Clearing House
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National biosafety systems
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Different systems:
• Guidelines and standards, e.g: Good Laboratory Practices
• Regulations - Pre-market regulations - Post-market regulations
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National biosafety systems
Stage Topic Mechanism
Laboratory research
- Workers protection- Environmental
safety
- Laboratory requirements
- GLP
Field Trials - Environmental safety
- Permit
Placing on the market
- Environmental safety
- Food/Feed safety
- Pre market approval/ deregulation
- Post market system
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Environmental Safety – Food/feed Safety
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Often different bodies involved, e.g:
- US: USDA, EPA, FDA
- EU: EFSA plus national authorities
Internationally agreed principles and methodology
•Environmental safety: Cartagena Protocol on Biosafety
•Food/Feed safety: Codex Alimentarius
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Environmental Risk Assessment - Methodology
Methodology
Procedure: Follow a number of steps
Substance: Take into account a number of parameters
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Environmental Risk Assessment - Methodology
1. Identification of relevant phenotypic and genotypic changes that may have adverse effects
2. Likelihood estimation
3. Evaluation of the consequences
4. Estimation of overall risk
5. Are identified risks acceptable or manageable?
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Environmental Risk Assessment - Methodology
Take into account the relevant characteristics of:
a. The recipient (host) or parental organism(s).
b. Inserted sequences.
c. The resulting GMO
d. The intended use (e.g field trial, commercial use)
e. The receiving environment.HORIZONS sprl
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Potential
adv. effects /
Likelihood
Estimation /
Evaluation of
Consequences /
Estimation of Risk /
Manageable acceptable ?
scientifically plausible
scenario
Highly likely
Likely
Unlikely
Highly unlikely
Major Intermediate
Minor
Marginal
High
Moderate
Low
Negligible
Toxicity
Non target effects
Weediness
Et cetera
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Environmental risk assessment
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Food Safety Assessment
Codex Alimentarius
Foods derived from biotechnology
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Guidance: European Food Safety Authority (EFSA)
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Comparative GMO food/feed safety assessment
Two main elements:
1. Intended changes: • The inserted genes and related traits• Assess intrinsic properties and functions of the
gene-product – tiered approach
2. Possible unintended changes in the GMO • as result of insertion or expression• Assess composition
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1. Intrinsic properties and functions of the gene products
Assessment of:
– Possible changes in toxicity
– Possible changes in allergenicity
– Case-specific topics, such as nutritional changes
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Step 1: For each newly expressed protein:
1. Molecular and biochemical characterisation
2. Computer-aided comparison of homology with known toxins
3. Digestibility in laboratory assay
Toxicity
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Step 2: In cases indicated by step 1, and in specific cases whereby the composition of the GM plant is modified substantially.
• Animal toxicity tests with pure protein
• Whole food/feed testing:– Laboratory animal toxicity tests (e.g. 90 days test) – Complex mixtures - More difficult to test than
purified chemicals
Toxicity
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General:
• Not an intrinsic, fully predictable property of a given protein
• Airway-, contact-, and food-allergies
• Food– "Big eight“ food allergens (90%)– All food allergens are proteins
Allergenicity
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Assessment of possible allergenicity
1. Is the donor of the novel gene a known allergen?
2. Comparison with known allergens - databases
3. In vitro digestibility and processing stability
• When indicated by the above (‘weight of evidence’): further testing, case by case:– Reaction with antisera from allergic patients– Clinical tests, such as skin prick test– Animal models
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Case-specific issue: Nutritional assessment
• Food/feed contains nutrients, antinutrients which may be target of modification
• In those cases: assessment of nutritional value– Calculated from compositional data– Domestic and laboratory animal feeding studies
(NB: these are not toxicity studies)
• Animal models– Chicken (rapidly growing)– Others, such as milk cows
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2. Unintended changes: compositional analysis
• Macro/micronutrients, anti-nutrients, toxins, and compounds from relevant metabolic pathways– Key parameters differ between organisms– Parameters in OECD consensus documents
• Assessment– Comparison with appropriate comparator(s)– Multiple seasons and locations (crop)
• Identify differences that are relevant to food/feed safetyHORIZONS sprl
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Experiences with GM crops to date
• 87-fold increase in hectares since 1996.
• Aggregated data indicate– Reduced production costs (50%),– Yield gains of 167 million tons; equivalent with
62.6 million additional hectares – pesticide reduction estimated at 356 million kg of
active ingredient– Reduction of fossil fuel use
Source: ISAAAHORIZONS sprl
Experiences with GM crops to date
• No verifiable reports of adverse effects of GM crops on human health or the environment –
• NB: Less mycotoxin contaminations in insect resistant crops due to reduced damage by pest insects
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Summary
• Genetic modification is tool that allows traits to be introduced in crop plants in a very targeted way and with a much greater reservoir of genes
• Although not a “silver bullet”, GM can help developing crops that produce more, that are less dependent on water, pesticides and fertilisers, that are more nutritious, and that have a longer shelf life
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Summary
• Internationally agreed methodologies are applied to assess the environmental and food safety of GM crops.
• The GM crops that are on the market to day are as safe as their non modified counterparts.
• Data show rapid global expansion of the adoption of GM crops by farmers, and substantial increases in yield, and reduction of use of pesticide and fossil fuels.
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Thank you
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