Risk assessment: Bt corn MON810

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Risk assessment Bt corn MON810 Risk assessment
identifying and evaluating possible
dangers predicting the chances the danger
will occur assessing the extent of damage
should the danger occur
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Risk or safety assessment AO 8 science-based tr
ansparent case by case by transformation
event Absence of scientific evidence is not
construed to imply safety nor danger Risk
assessment is revisited if new evidence is found
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Concept of substantial equivalence underlies
risk assessment Substantial equivalence
identifying and evaluating danger by comparing
Bt corn MON810 with a suitable
comparator Comparator isogenic line,
average of trait among various
varieties
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• Sources of risks
• The host plant
• The donor organisms
• The transformation system
• The inserted DNA
• The genetic stability of the
• introduced trait
• 6. The inserted gene product
• ( expressed material)
• 7. Potential for toxicity of the
• expressed material

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Sources of risks 8. The potential for
allergenicity of the expressed material 9.
The nutritional profile 10. Host plant
environmental assessment 11. Gene
transfer to related plants 12. Gene transfer to
unrelated organisms ( horizontal gene
transfer) 13. Weediness potential 14. Secondary
and non-target adverse effects
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• Host plant corn
• safety of corn as food, as feed
• Is there a history of safe use?
• Does corn contain any anti-
• nutrient?
• Does it contain a native toxin or a
• native allergen?
• How is corn used? Does processing
• change its nutritional profile?

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2. The donor organisms What are the donor
organisms and their donated genes? Toxicity
Is/are the donor organisms toxic? Do they
produce toxic substances? Are the
donated gene products toxic? Could
these new gene products interact to become
toxic?
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2. The donor organisms Allergenicity Is/are the
donor organisms allergens? Do they
produce allergens? Are the donated gene products
allergens? Could these new gene
products interact with other usual substances
to become allergenic?
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The transformation system Particle bombardment
vs. Agrobacterium transformation Indirect
effects due to the system action of
extraneous genes linked to the target
trait, genomic modifications and rearrangements,
pleiotropic effects Particle bombardment
- riskier
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The inserted DNA How much is inserted? Only the
target gene? How many copies? Target genes and
selective markers e.g. antibiotic
resistance genes? Where is the gene inserted?
Can Insertion affect increased production of
native allergens? native toxins?
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Genetic stability of introduced
trait Emphasis on trait not DNA Is the trait
expressed from generation to generation? Is
the expression of the trait through generations
the same?
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The expressed material/effects Characteristics
of the expressed material size of the
protein, physicochemical characteristics,
sequence, etc. Level location of the protein
levels in target/edible tissue, Bt protein level
in leaves efficacy Bt protein level in grain
food safety
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Toxicological assessment Bt DNA insert not
issue Bt protein expression in edible tissue,
processing effects on Bt protein, history of
protein, structure compared with known
toxins, physicochemical properties tolerance
to heat, digestibility Bt corn feeding
studies
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Allergenicity Bt protein source organism
expression in edible tissue, immunoreactivity,
sequence compared with known allergens,
physicochemical properties Heat/processing
stability, digestibility, effect of pH
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Nutritional data Comparative analysis of Bt corn
MON810 and isogenic lines and other
commercial varieties
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The host plant environmental Assessment Famili
arity with corn reproductive biology,
occurrence of natural hybrids with wild
relatives, interaction with other
organisms, origin, presence of feral types,
common pests and diseases Agricultural practices
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• Horizontal gene transfer
• examine data on presence of
• antibiotic resistance genes in
• Bt corn MON810
• Effect on non-target organisms
• Use of indicator species, field
• trials data effects on population
• of beneficial arthropods

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Weediness potential Assess whether Bt gene
affected the following Dissemination of
seeds Dormancy of seeds Competitiveness Agronomic
characteristics e.g. time to maturity, disease
and pest resistance
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Unintended effect Development of insect
resistance to Bt protein Possibility of
resistance development 100 Mitigating
measure protect Bt technology Insect
Resistance management IRM
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Thank you for your kind attention