GMOs Genetically Modified Organisms

1
GMOs Genetically Modified Organisms
Broadly defined any microbe, plant, or animal
developed through breeding and
selection Narrowly defined organisms produced
by gene transfer techniques
Current examples of GMO Crops

• insect-resistant crops
• cotton
• potato
• corn

• herbicide-resistant crops
• soybean
• corn
• canola (rapeseed)
• many others

GMO Crops on the Horizon
Corn, soy, canola with improved
nutritional qualities for animal
feed Crops with specialty starches and oils for
industrial processes
Nutraceuticals Golden Rice Vaccines in
plants Improved yields and stress tolerance
2
PLANT GENETIC ENGINEERING

• Product Concepts and Technical Feasibility
• Building the Transgenes
• Plant Transformation
• Event Selection
• Plant Breeding
• Seed Production and Marketing
• Detection of GMO Crops in the Commodity Chain

3
Product Concepts and Technical Feasibility

• Market potential for GMO Crop
• alternatives for production inputs
• enhanced storage stability
• improved nutritional or processing qualities

• Can the desired traits be engineered?
• How many genes must be introduced?
• Where must gene be expressed?
• appropriate organs, tissues, developmental stage
• localization within the cell
• Are genes and expression elements available to
  
• modify trait?
• Will there be interactions with other genes?

4
Building the Transgenes
ON/OFF Switch
Makes Protein
stop sign
Plant Transgene
5
Plant Transformation
The introduction and expression of genes into
plants is a three step process
DNA Delivery to Target Cells
6
Plant Transformation DNA Delivery
microprojectile bombardment biolistics or gene
gun
tiny DNA-coated particles are shot into plant
cells versatile method complex DNA integration
patterns tandem arrays of fragmented molecules
7
Plant Transformation Target Cells
All Crop Transformation Protocols Deliver
DNA to Plant Cells in Tissue Culture
Tissue cultures allow regeneration of fertile
plants from single cells Large number of target
cells available for DNA delivery in a compact
form (callus) Establishment, maintenance and
plant regeneration is labor intensive Methods
limited to a few genotypes, usually not
commercial varieties Can introduce undesirable
mutations
8
Plant Transformation Selection

• At best only 1 in 1000 cells integrate delivered
  DNA
• Transformed cells (events) are marked by
  co-introducing gene that provides resistance to
  selective agents
• Transformed cells are selected by killing
  non-transformed cells with selective agent.
• Three main types of selective agents
• antibiotics
• herbicides
• plant growth regulators
• Selectable markers assist in following
  inheritance of transgenes.

tissue culture cells under selection
9
Event Selection

• Goal Identify transgenic lines that stably
  exhibit
• desired phenotype
• Typically only 1 in 100 events are commercialized
• Transgene expression varies with chromosome
  position
• Complex transgene insertions are generally
  unstable
• gene silencing
• recombination within integrated transgene DNA
• Transgene cannot have negative effects on other
  plant
• phenotypes
• Transgenic line must satisfy regulatory
  requirements
• USDA, EPA, and FDA each review product
• no novel toxic or allergenic proteins or
  metabolites

10
THE MAKING OF A GMO CROP VARIETY
Backcrossing and selection (6- 8 generations)
x
x
x
Transgenic line
Commercial variety
Commercial Transgenic Line
Biotechnology
11
Seed Production
Target of 0.5 of U.S. Corn or Soybean Market
80 million acres x 0.005 400,000 acres Corn
(Cross-Pollinated Hybrids) Planted at 30,000
plants/acre 12 billion hybrid seed Need 300
million seed of each inbred parent Requires two
field seasons to generate enough seed, one season
to produce hybrid seed Soybean (Self-Pollinated
Varieties) require 3 seasons to generate enough
seed Maintaining Quality Control is a
Challenge!!!
12
GMOs Why the Controversy?
Genetic engineering is a powerful new technology
that is in general poorly understood and whose
long term effects are unknown. GMOs are an
innovation that have and will continue to impact
all facets of the global agricultural economy.
Processing
Production
Consumer Products
Commodity Handling
13
GMO Crops Three Major Issues
1. Food safety and environmental impacts 2.
Global trade 3. Increased corporate control of
agriculture
14
GMOs and Food Safety

• Genetic engineering creates novel genetic
  combinations
• Potential exists for undesirable effects of
  allergenicity or toxicity
• All GMOs are tested extensively for food safety
  prior to sale
• foods for human consumption and animal feed
• agricultural products (meat, dairy, fresh
  produce)

To Label or Not to Label? Labels must give
accurate information on product
composition Identity preservation methods,
tolerances, costs
15
GMOs and Environmental Impacts

• Genetic engineering creates novel genetic
  combinations
• All GMOs are tested for potential environmental
  impacts prior to sale
• influence on soil and water composition
• insect resistance management
• gene/trait transfer to weedy relatives
• interactions with agricultural environment

• GMO Crops Have Many Significant Environmental
  Benefits
• Reduced chemical pesticide and herbicide use
• More sustainable pest management
• Better erosion control through no-till practices
• Increased efficiency of production / unit fossil
  fuel energy expended

16
GMOs and Global Trade

• GM Commodity Crops Highlight Differences in
  Culture and Economic Systems
• Education level and awareness of agriculture and
  biotechnology
• Feelings toward food and agriculture as a way of
  life
• Governmental policies on the regulation of GM
  crops imports, sales
• Agricultural economies

17
Increased Corporate Control of Agriculture

• The Development of GM Crops is Expensive
• Intellectual property and patent protection
• Consolidation/vertical integration increases
  ability to capture profits

Ag-biotech is a recent example of a century-old
trend