Genetically modified food crops and their contribution to human nutrition and food quality

1. GENETICALLY MODIFIED
FOOD CROPS AND THEIR
CONTRIBUTION TO
HUMAN NUTRITION AND
FOOD QUALITY

2. WHAT IS DNA?
 DNA is molecule of life.
 It contains all of instructions (genes)
required to make an organism.
3

3. MODIFYING GENES
 Also called recombinant DNA technology,
molecular cloning, and genetic engineering.
1. Restriction enzymes are used to “cut” DNA
segments from one genome.
2. DNA ligases are used to “paste” them into
another genome.
Foreign
DNA

4. GENETICALLY MODIFIED (GM) CROPS
 What is a GM crop?
 GM crops are genetically improved and contain
a gene or genes from the same or a different
species artificially inserted in its genome.
 Tissue Culture & Transformation – gives the
maximum flexibility for moving genes within or
between species.

5. WHAT ARE GENETICALLY MODIFIED FOODS?
 Also called genetically modified organisms (GMO).
 Involves the insertion of DNA from one organism into
another OR modification of an organism’s DNA in
order to achieve a desired trait.
+
A strawberry
resistant to frost
=
4 5
Arctic fish DNA strawberry

6. EXAMPLES OF GMO’S
 Golden rice – rice that contains beta-carotene
(Vitamin A), which is not found in regular rice.
 Bt corn – corn that contains a chemical normally
found in a bacterium (Bacillus thuringiensis) that is
toxic to insects but not to humans.
 Herbicide resistant plants.

7. Golden rice
*Expression of enzymes
of β-carotene
pathway in rice
endosperm
*Amelioration of
Vitamin A deficiency

8. Bt-cotton - First GM crop – 2002
Second in global cotton production
Area – 8.0 million hectares – 2008
Yield gain - 31%
Reduction in pesticide sprays – 39%
Bt- COTTON

9. BT BRINJAL: PUTTING SCIENCE INTO AGRICULTURE

10. HOW ARE PLANTS TARGETED?
 A particle gun is used to shoot small
bits of metal coated with the gene into
the plant.
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11. HOW COMMON ARE GM FOODS?
48 foods
have been
approved for
use by the
Canadian
Food
Inspection
Agency.
Products
Corn
Canola
Potatoes
Tomatoes
Squash
Soybeans
Flax
Cottonseed oil
Sugarbeets
Derived Products
Corn syrup
Tofu
Canned foods
Soya sauce
Animals that feed
on GMOs…
….
AND MORE
Details can be found at: http://www.hc-sc.gc.ca/food-aliment/mh-dm/ofb-bba/nfi-
ani/e_novel_foods_and_ingredient.html

12. HOW COMMON ARE GMO FOODS?
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Labeling of GM foods is not mandatory unless if
there is a health or safety concern (Health
Canada/Canadian Food Inspection Agency)

13. THE ROLE OF BIOTECHNOLOGY
 Raise the yield ceiling and provide sustainable
production systems
Agriculture
Resource Based Science Based Industry
Food Security ??

14. TRANSGENICS
Insect pest resistance
• Stem borer
 Rice
 Sorghum
 Maize
• Pod Borer
 Pigeon pea
 Chick pea
• Boll worm
 Cotton
• Fruit borer
 Tomato
 Brinjal
• Aphid
 Brassica
Drought stress
Brassica
Delayed ripening
 Tomato
Fungal resistance
Rice
Banana
Virus
resistance
Cotton
Soybean
Tomato
Potato
Banana
Papaya
Cassava
TARGET CROPS ANDTRAITS
IN THE ICAR NETWORK

15. 22 COUNTRIES, 117.7 M HA
21 crops, 107 events, 539 approvals,
29 countries

16. 0
10
20
30
40
50
60
Soybean Maize Cotton Canola
Acreage of GM crops (Million ha)
Data: Clive James 2006

17. 0.80 M Ha
3.0 M Ha
Total plantation in India = 8.0 M Ha
1.40 M Ha
0.80 M Ha Others
1.6 M Ha

18. POTENTIAL BENEFITS
Humanitarian:
Improved
farming
Cheaper
food
More
food
Increased nutrition
Reducing
world
hunger
and
improving
world
health
Pest resistance
Herbicide
resistance
Cold tolerance
Drought
tolerance
Edible vaccines
Environmental: reduced use of herbicides
and chemicals in farming.

19. GENETIC MODIFICATION POTENTIAL:
 Reduced farming inputs:
 Reduced tillage
 Reduced use of pesticides, herbicides
 Improved yields
 Ability to grow crops in inhospitable environments
 Improved nutrition attributes
 Improved processing characteristics
 Prevention of loss of species to endemic disease

20. POTENTIAL ENVIRONMENTAL HAZARDS
Reduced
effectiveness of
pesticides as
insects become
resistant to
engineered toxins.
Loss of
biodiversity
Harm to other organisms
Pollen from Bt corn was shown to
cause high mortality rates in
monarch butterfly larvae(9). BUT
follow-up studies have shown
that the exposure levels in the
fields are negligible(10).
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21. POTENTIAL ENVIRONMENTAL HAZARDS
Gene Transfer to non-target species
 Herbicide resistant plants and weeds could cross
breed and create “superweeds”
 To address this one could:
 Create sterile male plants that don’t produce pollen
 Engineer the plants so that pollen doesn’t contain the
foreign genes
 Create buffer zones of non-GM crops around GM crops.
The buffer crops would not be harvested.

22. POTENTIAL HUMAN HEALTH RISKS
Allergens
 Genetic engineering could potential introduce
or create allergens
 For example, inserting genes from a nut into
another plant could be dangerous for people
who are allergic to nuts
Unknown health risks
 Biological processes involve a lot of
INTERACTIONS
 It is often difficult to identify every possible
interaction.

23. ECONOMIC HAZARDS
 Elimination of competition
 GM seeds are patented
 Suicide seeds
 Plants with sterile seeds that are infertile are created
 Farmers are forced to buy seeds every year
 However, some companies have reduced costs or donated
GM seeds to impoverished nations.

24. CREATING A BALANCE
 So are GM foods a
good or bad thing?
 It depend on each
individual case.
 Consumers, the
government and
scientists should be
responsible for
weighing the
benefits against the
costs.
Improved Nutrition
Resistance to disease
Reduced use of
chemicals
Environmental risks
Health risks
Economic risks

25. THANK YOU