GM FOOD COMPOSITION
FW Jansen van Rijssen PhD
GMASSURE
GM Food Safety Training
23 – 25 Nov 2015
Cottonseed oil from GMO cotton?
4
Why compositional analysis of conventional
crops?
• Voluntary
– Trading
– Environmental impact
– Biological variation as benchmarks
• Regulatory
– Variety registration
– Labeling (Codex Alimentarius)
– Food safety
• Research
Conventional methods:
• COMPOSITIONAL ANALYSIS
– Concentration of components (nutrients, antinutrients, toxicants) and more recently more
awareness of allergens
• NUTRITIONAL ASSESSMENT
– In vitro assays (digestibility)
– Wholesomeness – nutritive value and
performance.
Tendency for more
detailed information
SEED
DEVELOPMENT
• Molecular Biology
• Genome plasticity
AGRONOMIC
AND PHENOTYPE
ASSESSMENT
• Comparative
analysis
• familiarity
FOOD ANALYSIS
• Codex
Alimentarius
• OECD
PROBLEM FORMULATION
FOOD
ANALYSIS
INTENDED/
UNINTENDED EFFECTS ?
FOOD COMPOSITION -SAFETY
ASSESSMENT OF GM FOODS
• FAO/WHO Codex Alimentarius Commission
ad hoc committee (1990 , 1996, 2000),
• OECD 1993 onwards
Test
• Critical compositional elements of
the modified variety
Comparator
• Non-GM variety with history of safe use
• Near isogenic line grown under identical conditions.
References
• Conventional varieties or hybrids that are grown
commercially in the geographies of the field trials.
Comparative approach
• Most appropriate strategy for the safety /
nutritional assessment of GM-food
• Focus on determination of similarities and
differences between GM-food and
conventional counterparts
• Not a safety assessment in itself but a key
step in the process of safety assessment
COMPOSITION
ANALYSIS
(EFSA, 2008)
CODEX ALIMENTARIUS
WORKING PRINCIPLES
FOR RISK ANALYSIS
TRANSGENES/GMO
COMPARATIVE APPROACH
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TARGETED APPROACH
Near(est) iso-line
Critical components
Characteristics of the crop
History of safe use
Safety assessment
HISTORY OF SAFE USE
• The USA Food and Drug Administration (USFDA): “generally recognized as safe” (GRAS) ‒
for food or food additives, which includes a
long history of use or by virtue of scientific
information about the nature of the
substances, their customary or projected
conditions of use, and the information
generally available to scientists about the
substances .
HISTORY OF SAFE USE
• The Organization for Economic Co-operation
and Development (OECD) accepts that a “long
history of use is a reassuring and practical
starting point” for evaluating the safety of GM
food and has prepared a number of guidelines
in this respect.
History of Safe Use
(Constable et al 2007)
• History: Correct identification; Biology (origin, genetic
diversity); Length of use; Geographic/demographic
distribution of use; Details of use; Evidence of adverse
effects; Reliability of data
• Safe: Composition (especially toxic, allergenic, metabolic,
nutritional and antinutritional components as well as
health compromising compounds). In silico tests (e.g.
structural homology to known allergens or known toxins);
In vitro tests (e.g. serum screening, digestibility tests);
Animal studies (toxicology and nutrition studies);
Experience from human exposure; Clinical studies;
Epidemiological evidence.
• Use: Type/purpose (e.g. as a food, ingredient, supplement
or pharmaceutical).
Safety:
• “..it is a judgment, it is value laden…
..understood within contexts of society,
culture, politics , and economics’ (Wolt, 2008)
• Reasonable certainty of no harm (OECD, 1993)
Risk:
• “ ..there is always a degree of risk..” (Wolt, 2008;
Querci et al., 2010)
“History of safe use”
of
CASSAVA
Containing
CYANOGENIC GLYCOSIDES ?
CYANOGENIC
GLYCOSIDES
(addendum)
CONSENSUS DOCUMENTS
Contents of consensus document
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ABOUT THE OECD
FOREWORD
PREAMBLE
THE ROLE OF COMPARATIVE APPROACH AS PART OF A SAFETY ASSESSMENT
ACRONYMS
SECTION I –BACKGROUND
1. General description of cassava
2. Production .....
3. Processing and Use
3.1 General human and animal consumption
3.2 Human food processing
3.3 Animal feed processing
3.4 Range of industrial food products
3.5 Ethanol production and animal feed by‐ products
4. Appropriate comparators for testing new varieties
5. Breeding characteristics screened by developers ..
SECTION II –NUTRIENT
1. Unprocessed roots and leaves .
1.1 Proximate composition
Contents of consensus document
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1.2 Carbohydrates
1.3 True protein (amino acids)
1.4 Lipids
1.5 Minerals
1.6 Vitamins
2. Processed cassava products
SECTION III –OTHE CONSTITUENTS R
1. Anti‐nutrients
1.1 Tannins
1.2 Phytic Acid
1.3 Oxalate, Nitrate, Polyphenol, Saponin, Trypsin inhibitor
2. Toxicants
3. Allergens .
SECTION IV‐ SUGGESTED CONSTITUENTS TO BE ANALYZED RELATED TO FOOD USE
1. Food uses and products
2. Suggested analysis for food use
SECTION V ‐ SUGGESTED CONSTITUENTS TO BE ANALYZED RELATED TO FEED USE
1. Livestock feed uses
2. Suggested analysis for feed use
SECTION VI – REFERENCES
Food constituents to be analysed in fresh roots
and leaves of cassava (OECD, 2009)
Constituent/analytes
Proximate
Fresh leaves
Fresh roots
X
X
Starch
X
Fatty acids
X
X
Amino acids
X
X
Mineral
X
Vitamins
X
X
Cyanogenic glycosides
(linamarin and lotaustralin)
X
X
HCN
X
X
Tannins
X
Phytic acid
X
FOCUSSED APPROACH
“SEARCH LIGHT”
X
Feed constituents to be analysed in fresh roots
and leaves of cassava for f(OECD, 2009)
Constituent/analytes
Proximate
Fresh leaves
Fresh roots
X
X
Starch
X
Acid detergent fibre
X
X
Neutral detergent fibre
X
X
Calcium
X
Phosphorous
X
Cyanogenic glycosides
(linamarin and lotaustralin)
X
Tannins
X
Phytic acid
X
X
VARIATION OF NUTRIENT CONTENTS
IN FOODS (INFOODS)
Nutrient contents in foods can vary significantly
because of:
environmental, genetic and processing influences
such as
feed, soil, climate, genetic resources
(varieties/cultivars, breeds), storage conditions,
processing, fortification and market share;
Distribution of Maize Protein Values in ILSI
Database
Distribution of Protein Values in ILSI Database
50
45
Number of Samples
40
35
Argentina
EU
30
United States
25
20
15
10
5
0
5
7
9
11
Protein (% dw)
13
15
17
Natural Variability – Conventional Maize
Hybrids
30
7 Varieties, 6 Locations, 1 Year
25
20
15
10
5
0
Asp Thr Ser Glu Pro Gly Ala Cys Val Met Iso Leu Tyr Phe His Lys Arg Trp
Amino acids
(Reynolds et al., 2005).
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Changes within
this range are
normal (and safe)
Isoflavones in soybean

Are physiologically active
Variety
Place
mg isoflavones/10 g
Hardin
Hardin
Hardin
Hardin
Girard, IL
Urbana, IL
Pontiac, IL
Dekalb, IL
47 a
82 a
156 b
171 b
Hardin
Amcor
Century
Sprite
Urbana, IL
Urbana, IL
Urbana, IL
Urbana, IL
116
150
250
309
a
b
c
d
Parrot
- OMIC: Metabolic Pathways
Number of publications comparing GM and non-GM crop
varieties with or without intentional metabolic changes
(Ricroch et al., 2011)
Number of crop
plants
Metabolic
changes
Not metabolic
changes
10
25
19
• Natural variation explain most transcriptomic changes among
maize plants.... (Coll et al., 2010)
• Gene expression profiles of GM.... Comparable with nonGM...” (Coll et al., 2009)
• Micro-array analyses reveal that plant mutagenesis may
induce more transcriptomic changes than transgene insertion
(Batista et al., 2008)
• Transgenesis has less impact on the transcriptome of wheat
grain than conventional breeding (Baudo, 2006)
• Global transcriptome profiling is a poor predictor of the
secondary effects of transgene influencing abiotic stress
tolerance (Chan et al., 2012)
Increased safety assessment?
Single traits
Stacked
traits
?
Comparative
approach
Compositional
assessment
Metabolic
pathways
Metabolic
pathways
Nutritionally
enhanced /
abiotic stress
Comparative
approach
Compositional
assessment
PLACE FOR / OF OMICS
- STUDIES ?
Metabolic
pathways
Metabolic pathways
References
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Constable, A, Jonas, D, Cockburn, A, Davis, A, Edwards, G, Hepburn, P, ..., Samuels,
F 2007, ‘History of safe use as applied to the safety assessment of novel foods and
foods derived from genetically modified organisms’, Food and Chemical Toxicology,
vol. 45, pp. 2513–2525
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Rachel S. Meyer1,2, Ashley E. DuVal3 and Helen R. Jensen (2012)Patterns and
processes in crop domestication:an historical review and quantitative analysis of
203 global food crops ,New Phytologist ,196: 29–48
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