Genetically modified foods are foods that have had their DNA altered through genetic engineering to contain added or deleted gene sequences. They may contain genes from other organisms to produce a desired trait. Genetic engineering allows for more precise and rapid alteration of organisms compared to traditional breeding methods. Common genetically modified foods include vegetables, tomatoes, potatoes, rice, cheese, and meat. While GM foods could help address world hunger and develop more resilient crops, there are also risks like insects developing pesticide resistance or cross-pollination creating "superweeds". Government agencies regulate GM foods to ensure safety.

1. GeneticallyGenetically
Modified FoodsModified Foods

2. What is a GeneticallyWhat is a Genetically
Modified (GM) Food?Modified (GM) Food?
 Foods that contain an added geneFoods that contain an added gene
sequencesequence
 Foods that have a deleted geneFoods that have a deleted gene
sequencesequence
 Animal products from animals fed GMAnimal products from animals fed GM
feedfeed
 Products produced by GM organismsProducts produced by GM organisms

3. Why are foodsWhy are foods
genetically modified?genetically modified?
Genetic engineering offers a rapidGenetic engineering offers a rapid
and precise method of alteringand precise method of altering
organisms as compared toorganisms as compared to
traditional methods that are slowtraditional methods that are slow
and inaccurate.and inaccurate.

4. Common GM FoodsCommon GM Foods
 VegetablesVegetables
 TomatoesTomatoes
 PotatoesPotatoes
 RiceRice
 CheeseCheese
 MeatMeat

5. How is geneticHow is genetic
modification possible?modification possible?
 The components ofThe components of
DNA are the sameDNA are the same
in all organisms.in all organisms.
*Remember this*Remember this
from last unit???from last unit???
 Sequences thatSequences that
code for proteinscode for proteins
can be moved fromcan be moved from
one organism toone organism to
another.another.

6. How can DNA be movedHow can DNA be moved
from one organism tofrom one organism to
another?another?
►Find an organism with the desired
trait
►Isolate the gene sequence that
codes for the desired trait
►Insert the gene sequence into the
genome of the plant cell

7. How can DNA be movedHow can DNA be moved
from one organism tofrom one organism to
another?another?
Its quite
simple,
REALLY!!!

8. How can DNA be movedHow can DNA be moved
from one organism tofrom one organism to
another?another?
►Allow the genetically
altered cell to grow into a
plant
►Allow the plant to reproduce

9. How can DNA be movedHow can DNA be moved
from one organism tofrom one organism to
another?another?
 A vector canA vector can
carry DNA. Thecarry DNA. The
vector can be avector can be a
pellet from apellet from a
gene gun.gene gun.
Viruses andViruses and
bacteria alsobacteria also
can be utilizedcan be utilized
to transferto transfer
genes.genes.Watch the clip to demonstrate the process.
http://www.dnalc.org/view/15476-Mechanism-of-Recombination-3D-animation-with-with-basic-narration.html

10. Possible BenefitsPossible Benefits
of GM Foodsof GM Foods
 Easing of worldEasing of world
hungerhunger
 Development of cropsDevelopment of crops
that can be grown inthat can be grown in
marginal soilmarginal soil
 Reduced strain onReduced strain on
nonrenewablenonrenewable
resourcesresources
 Development of droughtDevelopment of drought
resistant cropsresistant crops
 Development of salt-Development of salt-
tolerant cropstolerant crops
 Development of cropsDevelopment of crops
that make more efficientthat make more efficient
use of nitrogen and otheruse of nitrogen and other
nutrientsnutrients

11. Possible BenefitsPossible Benefits
of GM Foodsof GM Foods
 Reduced use ofReduced use of
pesticides andpesticides and
herbicidesherbicides
►Development ofDevelopment of
pest resistant cropspest resistant crops
►Reduced herbicideReduced herbicide
use is better for theuse is better for the
environment andenvironment and
reduces costs forreduces costs for
farmersfarmers

12. Possible BenefitsPossible Benefits
of GM Foodsof GM Foods
 Improved crop qualityImproved crop quality
 Development of frost resistantDevelopment of frost resistant
cropscrops
 Development of diseaseDevelopment of disease
resistant cropsresistant crops
 Development of floodDevelopment of flood
resistant cropsresistant crops
 Improved nutritionalImproved nutritional
qualityquality
 Development of foods designedDevelopment of foods designed
to meet specific nutritional goalsto meet specific nutritional goals

13. Who makes sure GMWho makes sure GM
foods are safe?foods are safe?
 GovernmentGovernment
agencies regulateagencies regulate
GM foodsGM foods
 GM foods in theGM foods in the
United States areUnited States are
required to be labeledrequired to be labeled
only if the nutritionalonly if the nutritional
value is changed or avalue is changed or a
new allergen isnew allergen is
introduced.introduced.

14. Possible RisksPossible Risks
of GM Foodsof GM Foods
 Insects mightInsects might
develop resistancedevelop resistance
to pesticide-to pesticide-
producing GMproducing GM
cropscrops
 Herbicide-tolerantHerbicide-tolerant
crops may cross-crops may cross-
pollinate weeds,pollinate weeds,
resulting inresulting in
"superweeds""superweeds"

15. Possible RisksPossible Risks
for GM Foodsfor GM Foods
 Certain geneCertain gene
products may beproducts may be
allergens, thusallergens, thus
causing harm tocausing harm to
human healthhuman health
 There may beThere may be
unintended harm tounintended harm to
wildlife andwildlife and
beneficial insectsbeneficial insects
Photo courtesy of T. W. Davies, Cal. Acad. of Sciences.

16. Time to ThinkTime to Think
• What is a genetically
modified food?
• What are some benefits of
genetically modified foods?
• What are some possible risks
of genetically modified food?