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Nuts and Bolts GMOs
Harold Trick
Department of Plant Pathology
Kansas State University
Manhattan, KS
Part I: The Science of GMOs
Presentation to Women Managing the Farm
Conference – Kansas 2/10/2017
Topics Addressed:
• What are GMO or GE organisms?
- (Definitions)
• How are GMO (GE) crops made?
• Why do we make them?
• Are they safe?
• How are they regulated?
•What GE crops are on the market?
Percentage of Biotech Acreage in USA
Source: Agricultural Statistics
Board USDA-ERSFarmer benefits: herbicide and insect resistance
What Is a GE or (GMO)?
• A genetically engineered
organism is a living plant,
animal, or microbe that
incorporates laboratory-
made recombinant DNA.
• Same as “transgenic”
• Less correctly referred to
as “Genetically Modified
Organism” or GMO
Genetically
Engineered
Organism
• chemical substance of genes
• assembly instructions for proteins
• genetic code is part of each
strand of the double helix
• the instruction code is
universal !!!!
G--C
A--TC--G
A--T
A--T
T--A
C--G
C--G
What is DNA?
What is a Gene?
GenePromoter
DNA RNA Protein
Desired trait
Terminator
DNA Sequence
tells the cell where and
how of product to make
Recombinant DNA
+ =
Cut and pasted
artificially in
the lab by
molecular scissors
Bacterial
DNAPlant
DNA
Plant DNA with
a small piece of
bacterial DNA
Glow in
the dark
tobacco
plant
stem
roots
leaf
Pharmaceuticals
Most if not all insulin on the market today is a GE product
Roundup Ready Soybeans
Conventional Roundup
Ready
Plant Transformation
Lab and Field testing
Breeding Program
Public Release
Gene Modification
BASIC
APPLIED
Research Steps
Gene Discovery
How to get the Gene into the plant ?
Inductio
n CM4
Proliferatio
n
Development
MSP
Regeneration
MSE
Plant Recovery
Starting
Material
Wheat
Tissue cultureModified MS-based medium w/
0.5 mg/L 2,4-D + 2.2 mg/L
picloram
10-14 d post anthesis
Modified MS-based medium w/
0.2 mg/L 2,4-D
Modified MS-based medium
no hormones
Agrobacterium Particle gun
Plant
Transformation
The Gene Gun
Plant tissue
DNA
Particle Bombardment
Nucleus
Target Cell
Metal particle
DNA
Wheat embryo tissue
transformed with
DNA
GFP:Green Fluorescent Protein
Shows the EVENTS
Wheat shoot stably
transformed with
GFP
Regeneration of Plants
GMO Wheat Plant Ready to
Test
TransgenicControl
sprayed with 0.2% Liberty
Why Do We Do It?
• To research gene function
• To deepen the gene pool and gain access
novel traits
• To gain greater control of trait expression,
including knocking out genes
• To cheaply manufacture expensive or rare
proteins (plantibodies, vaccines)
• Food Security
Agricultural Biotechnology or Genetic Engineering can
help increase our food supplies by providing protection
against various stresses
• Limited starch deposition
under high temperature
• Soluble starch synthase
(SSS)- heat liable
Seed size/yield is sensitive to heat
65 °F 77 °F 95 °
Effects of temperature on seed size
• Climate Models predict that Extreme Heat will occur every
1-3 years in the U.S
• Every 2°F rise above 65°F results a ~3-6% loss in yield
potential
• Total 2015 US wheat production 2.1 billion bu. (USDA,NASS)
• (wheat grown at 77°F results in 20-38% yield penalty)
0
5
10
15
20
25
30
35
40
88 °F 91 °F 93 °F
Perc
ent Y
ield
Incre
ase
Com
pare
d t
o C
ontr
ol P
lants
Plant expressed
**
**
**
**
*
Validation: Plants expressing heat tolerant protein significantly outperforms controls
Control
non-transgenic
Seeds harvested from 93 °F heat treatment
Seed expressed trait
Plant expressed trait
GM Traits: the benefits
• Herbicide
resistance
• Insect resistance
• Disease resistance
• Pollen sterility
• Salt, cold or
drought tolerance
• Altered ripening
• Nutritional content
• Allergen content
• Altered oil content
• Anti-oxidants
Part II: Benefits and Risks of GMO's
Bt Sweet Corn
• Conventional sweet corn sprayed multiple
times with insecticides for corn earworms.
Transgenic Papaya Resistant to PRSVPapaya Ringspot Virus
http://www.planthealthprogress.org/current/reviews/papaya/top.htm
Golden Rice: A Functional Food
• Vitamin A
deficiency causes
blindness in some
countries
• Beta carotene
(provitamin A)
from daffodil
Risks of GMOs
Risk Analysis
• Hazard identification
• Hazard severity (worst case scenario)
• Probability of hazard
• Steps available to reduce risk
• Risk balancing (risk/risk and risk/benefit trade-offs)
• What is the acceptable risk level (margin of safety)
The public is bombarded with
misinformation on GE crops
The public is bombarded with
misinformation on GE crops
- rat study retracted
- control rats also had tumors
9/19/2012
Does GM plants cause autism??
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What are the risk with
Genetically engineered crops?
• Environmental
• Health
National Academy of Science, World Health Organization and British
Royal Society: Risks of GMOs are no different than conventional
organisms
What are the Environmental Issues?
• Loss of effectiveness of Bt pesticide due
to over-use
• Non-target effects
• Escape of transgenes
Bt-toxin• Bacillus thuringiensis (or Bt)- Gram + soil
bacterium that produces a protein toxin (cry)
• Considered environmentally friendly
– Effect specific classes of insects
– No effect on mammals or honeybees
• 1901- bacteria was discovered to have cause
diseases in insects
• 1920’s- the bacteria were used as insecticides
• Currently used as an organic pesticide
Bt-toxin
• Currently used as an organic pesticide
• 1976 Bt gene was isolated
• 1985 first plant engineered to express
(tobacco)
• 1995 Bt engineered potato approve by EPA
• 1996 Bt corn, cotton, soybean and potatoes
grown
Loss of effectiveness of Bt
pesticide due to over-use
Cotton: Bollworm
Corn: corn borer
corn earworm
corn rootworm Soybean: bean looper
soybean moth
Positive environmental impact2001 North American Breeding Bird Survey:
Populations of songbirds that frequent around cotton
fields have increased significantly in the major U.S. cotton
producing states, with increases of 20 percent in Arizona,
over 30 percent in Mississippi and Alabama, and 10 percent
in Texas.
Quail nesting in cotton fields in south west, never
before seen
Environmental Protection Agency (EPA)
(2010):
“data provide a weight of evidence indicating no
unreasonable adverse effects of Bt proteins
expressed in plants to non-target wildlife”
Herbicide resistant plants
allows farmers to use “no till”farming practices
prevents erosion
conserves water
2003- Adoption of GE
plants resulted in a
reduction of 443 million
pounds of herbicides in
USA
What are the Health Issues?
• Eating “foreign” genes
• Toxins
• Nutritional content
• Allergens
• Medicines produced in plants
proteins
How can we ensure safety?
Biotech Regulatory Oversight
In US-coordinated approach
several agencies share responsibilities
-each product is regulated on a case-by-case basis
-government exercises oversight through a consultative process
USDA-APHIS
• Environmental
EPA
• Plant Pesticides
FDA
• Food
•Livestock feed
USDA-APHIS-
Regulation of confined
Trials
NIH and Institutional
Biosafety Guidelines
Research &
Development
Confined field trials
Food, Feed, &
Safety Assessment
7-10yrs, minimum
USDA-APHIS
• Environmental
EPA
• Plant Pesticides
FDA
• Food
•Livestock feed
USDA-APHIS-
Regulation of confined
Trials
NIH and Institutional
Biosafety GuidelinesResearch &
Development
Confined field trials
Food, Feed, &
Safety Assessment
Environmental Risk Assessment
Before a GE crop can be grown on a wide scale or sold
commercially, its developers need to petition APHIS for
“determination of non-regulated status”
1. Description of biology of non-modified plant
2. Relevant data and references
3. Complete a molecular characterization of GE plant
4. Detailed differences in genotypes between GE and Non-GE
5. Detailed differences in phenotypes between GE and Non-GE
6. Agricultural practices
7. Effects on non-target organisms
8. Indirect plant pest effects
9. Gene transfer potential between species which cannot interbreed
Solicitation of public comments in the Federal Registar
Food and Feed Safety Assessment
1. Purpose of intended modification
2. Complete a molecular characterization of GE plant
3. Information on expressed proteins
4. Information on known or suspected allergenicity and toxicity
5. Information on compositional and nutritional characteritics
6. For foods known to be allergenic, any change in endogenous
allergens
7. Comparisons of feeding studies comparing GM and non-GM
Solicitation of public comments in the Federal Registar
Overall time to Commercialization
13.1 years from the initiation of the discovery of a trait to
commercial launch of the transgenic plant in US
Canola Corn Cotton Soybean All
Crops
Years 11.7 12.0 12.7 16.3 13.1
This overall time can be broken down to two overall stages:
A. Research and development
B. Registration and regulatory affairs
R&D can further be broken down into subcategoriesSurvey by Phillips McDougall.2012
What is the Overall cost of bringing a GE event to the market?
Activity Stage
I. Early
Discovery
II. Late
Discovery
III. Construct
Optimization
IV. Commercial
Event Production
and Selection
V. Introgression
Breeding &Wide-
Area Testing
VI. Regulatory
Science
VII. Registration
& Regulatory
Affairs
Between 2008 and 2012 overall cost was $136 million
http://www.simplotplantsciences.com
(time.com)
Conclusions
• Genetic engineering is a powerful tool to
improve efficiency and nutrition of crops.
• There are legitimate concerns about risks
of GM crops that can be assessed.
• NAS: “risks do not differ in kind” from
conventional methods
• GMOs are not inherently safe or unsafe
• Products must be evaluated on a case-
by-case basis
2016 marked the 21th anniversary
of biotech crops on the market
• 181.5 million hectares (448 million acres)
have been planted Worldwide
• 18 million farmers in 28 countries plant
biotech crops
• Billions of people have consumed GE products
(even you)
• Cases of illness or deaths associated with GE
products: 0