Slide show on biotechnology by Jada Hueber (DIS Sp. `02)

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Transcript Slide show on biotechnology by Jada Hueber (DIS Sp. `02)

Biotechnology: reading between the lines of
science and safety
Why has regulation proved to be so difficult?
Jada M. Hueber
2002
Biotechnology: reading between the lines
of science and safety
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Where did genetic
engineering come from?
Where can we find
genetically modified
organisms today?
What are some reasons for
support / concern?
Are genetically modified
organisms regulated by
the government?
Is biotechnology safe?
Genetic Engineering: background
 1966 Marshall Nirenberg & Har Gobind Khorana finished
unraveling the genetic code.
 1973
Herbert Boyer & Stanley Cohen performed the first
recombinant DNA cloning experiment using restriction enzymes to
insert DNA into a plasmid and use the transgenic plasmid (a
circular bacterial 'chromosome') to transform bacteria.
 1980 U.S. Supreme Court rules that living organisms can be
patented.
 1983 First transgenic plant (tobacco).
 1985
First transgenic plant produced-- resistant against a
definite insect species.
 1987
A transgenic plant produced resistant to a particular kind
of herbicide.
GMO History continued...
 1988
First transgenic plant producing a pharmaceutical.
 1994
Transgenic tomatoes contain a softening inhibition gene.
These FlavrSavr tomatoes are sold in stores for a short time before
being taken off the market.
 1998
April, a UK supermarket chain bans use of GMOs in its
products, a move which over the following 18 months is followed
by the other UK supermarket chains. May, widespread
contamination of the UK canola crop by GM oilseed rape
contaminated seed imported from Canada by Advanta.
 Some sources cite Gregor Mendel, the Austrian Monk who studied
genetics in pea plants, as the first genetic engineer. This brings to
question, what is the difference between the modern science of
biotechnology and plant breeding for desired traits which has been
going on for centuries? Keep this question in mind...
The Science of Genetic
Engineering
making a modified gene
Isolate desired gene
(increased shine)
Isolate plasmid DNA
(apple)
Insert modified plasmid into
bacterium for replication.
Gene inserted into
plasmid.
Grow in culture to
replicate.
Making the transgenic cell…
GMOs!
Transfer copies into
carrier bacterium.
Transgenic cell
Transfer to soil…
...and growing
A. tumefaciens
(agrobacterium)
Cell division
Transgenic plants with
new traits!
Bacterium
inserts
DNA into
plant cell.
Grow cells in
culture to form
plantlets.
Where can I find GMOs?

All of these brands, and
many more, have been
identified as using GMOs
in their ingredients.
Sometimes, as in the case
of Gerber baby foods, the
product is found to contain
GMOs despite company
efforts to discontinue the
use of GM crops.
Kellogg’s, Kraft, McDonald’s, Nestle USA, and Quaker Oats all
sell foods with GM ingredients in the U.S. but not in their products
overseas where consumer opposition is strong.
The growing popularity of GE crops

In January, the
International Service
for the Acquisition of
Agri-biotech
Applications (ISAAA)
announced that global
acreage of GE crops
increased 19% in 2001
(130 million acres).

From 1998 to 1999,
global GE crop
acreage grew 143%.
Who grows GE crops?


Three countries
produce more than
95% of the GE crops
in the world;
Argentina, Canada,
and the United
States.
Only four crops are
currently being
grown on a large
scale: canola, corn,
cotton, and
soybeans.
What good are GMOs?
Imagine medicinal fruits that help prevent illness...
“Golden Rice” is engineered to contain beta-carotene, a
vital nutrient that can prevent blindness in malnourished
children.
Crops can defend themselves against pests and viruses, decreasing
the amount of chemicals used by farmers.
Crops can be engineered to thrive in previously inhospitable
soils, giving farmers in developing nations a livelihood.
Produce can be designed to be healthier, less fattening, etc...
Imagine food enough to feed the world...
Photos: www.thebiggestpixel.com/people01.html & www.picturesof.net
Substantial Equivalence: a new variety of food
must be as safe as traditionally bred varieties and foods.
Summary of safety assessment:

Compositionally equivalent to conventional varieties

Nutritionally equivalent and perform comparably to
conventional varieties in food production and for livestock and
poultry feed.

Contains protein that is proven safe for consumption.
Regulation jurisdiction: the Coordinated
Framework system
A) If the biotech product is a microbe, the EPA
regulates it.
B) If the biotech product is a plant or insect, USDAAPHIS regulates it.
C) If the biotech product is a food or medicine, the
FDA regulates it.
D) If the research was funded by the federal
government, the National Institutes of Health
(NIH) or USDA regulates the product of the
research.
The Four Principles of Regulatory Review
1) federal government regulatory oversight should
focus on the characteristics and risks of the
biotechnology product and not the process by
which it is created;
2) for biotechnology products that require review,
regulatory review should be designed to minimize
regulatory burden while assuring protection of
public health and welfare;
3) regulatory programs should be designed to
accommodate the rapid advances in biotechnology;
and
4) in order to create opportunities for the
application of innovative new biotechnology
products, all regulation in environmental and
health areas should use performance standards
rather than specific rigid controls or specific
designs for compliance.
Federal regulators seek to protect human safety,
intellectual property rights of individuals and
corporations, and the genetic integrity of existing
plant and animal species...
In 1980, the U.S. Supreme Court allows patents of living
organisms because biotechnology procedures had made
possible a human invention from a naturally-occurring
organism.
the conundrum
Genetically modified
organisms are
“substantially
equivalent” to
conventional varieties.
Therefore, they don’t
require labeling.
&
Genetically modified
organisms are not
“products of nature,” but
“human invention.”
Therefore, they are able
to be patented.
Corporate v. Consumer Demands:
labeling
The New York Times reported that a “biotech industry poll” showed that
93% of Americans wants genetically engineered foods labeled.
The American Government and the biotech industry are concerned that
labeling will be misleading to consumers, since they claim traditional
crops and GE crops substantially equivalent.
Consumer Advocates claim that the popularity of GMOs has to do with
the fact that consumers are not given the choice, because they are not
fully informed about what they are purchasing.
H.R. 3377 “Genetically Engineered Food Right to Know Act” label:
United States Government Notice: This product contains a genetically
engineered material, or was produced with genetically engineered
material.
Environmental issues
The biotech industry claims that
genetically modified organisms will
be good for the environment.
So why are environmentalists
worried?
“Biotechnology has the potential to create more and better
sources of food, to reduce pesticide use, increase yields, and
improve nutrition and quality of life.”
Dr. Sally McCammon, USDA Animal and Plant Health Inspection Service
12
10
8
6
RR corn
watersheds
N=131
other
watersheds
N=1,185
4
2
0
>4 ppb
>2 ppb
Studies reported by the
Monsanto Corporation
suggest that crops
engineered to be herbicidetolerant reduce the use of
agricultural chemicals, and
therefore, contamination of
the environment. This
practice of choosing the
best combination of tools
to control crop pests is
called Integrated Pest
Management (IPM).
“When I started farming 23 years ago we didn’t use the most powerful
chemicals on the market, we didn’t flood the land with fertilizer, and we
still made a good living...Our gross revenue to expense ratio was 3 to 1.
Today, we are on the cutting edge, using GMOs, changing crop varieties
almost yearly, using chemicals as if we farmed in Europe, and our revenue
to expense ratio has dropped to 1.25 to 1, on a good year, just enough to
pay the grocery bill.”
Lloyd Fear
Red River Valley, Manitoba
Growers planting RR crops have three choices regarding weed control:
• Apply early to avoid early-season yield losses from fast growing
grasses, possibly suffering yield losses from late season weeds;
• Delay applications until most weeds have germinated, risking loss of
yield to early weeds; or,
• Apply Roundup twice or more, and/or a residual herbicide at planting
or when Roundup is applied.
“It is not clear which are greater – the successes of modern highintensity agriculture, or its shortcomings…A greener revolution is
needed – a revolution that incorporates accumulated knowledge of
ecological processes and feedbacks, disease dynamics,
soil processes and microbial ecology” (Tilman 1998).
In one situation, after the first two applications of Roundup Ultra
(total of 60 oz/A) weeds had survived. They were eventually
controlled by a third application of 48 oz/A. Further tests were
done involving RR crops and weed management. The effective
rates were at or above typical field use rates (32 oz).
“Everyone expects that a higher percentage of soybean acres will
be planted to GMO varieties and that most farmers doing so will
need to apply two or three applications of two or more
herbicides.”
Charles M. Benbrook, PhD.
= the combined result of
survival, reproduction, and dispersal.
Without a quantitative estimate of spread, risk analysis is doomed to
anecdotal status
Asymptotic Rate of Spread (ARS)-- in units of distance/time, the rate at
which an gene’s aerial range increases in radius.
“Virtually all spread models predict that at first the observed rate of
spread will be slow and will gradually accelerate to some asymptotic
maximum rate. Thus, without some form of quantitative analysis, it is not
wise to conclude spread will be negligible simply because after one
generation, most genetically engineered organism or genes are
discovered close to their initial point of release” (Kareiva, et al. 1991).
Gene-Spread model: yellow circles spread and increase in frequency as a
result of dispersal and selection.
Spatial distribution of genotypes
Disperse pollen
Mating & seedling
production
Selection in favor of
get next generation
to
Spread is of particular concern regarding
biodiversity and the creation of “superweeds”...
Superweeds develop if herbicidetolerant modified crops crossbreed with weedy relatives.
The resulting plants would be
resistant to the herbicide.
S
The concern is similar for insects.
Will natural selection lead to a
population of insects unharmed by
modern pesticides?
In the field, nature’s predisposition to
adaptation has made things more complicated.
Initially it was stated that it was extremely unlikely that
Roundup resistance would appear in weeds. Shortly after
these statements were made the first case of Roundup
resistance appeared in Australia...
According to Bob Hartzer of Iowa State University:
Herbicide resistance is defined as the inherited ability of a weed
to survive a herbicide dose that kills the wild type of that
species.
The two important points of this definition are
1) the ability to survive the herbicide is genetic and passed along
to progeny, and
2) the native population is controlled by the herbicide.
RR
Researchers have documented glyphosate resistance in a
rye grass species.
Waterhemp was highlighted in the 1998 edition of the
Weed Control Manual as the most worrisome “Up and
Coming Weed” nationwide due to the emergence of
resistance to triazine and ALS herbicides and its ability to
withstand Roundup applications.
The Roundup Ready system cost an amazing $68.77 per acre in
1999. Fifty percent more than the cost of seed+weed management
systems in recent years, largely because farmers had to use more
chemicals.
“A pest management system that relies predominantly on
one tactic is inherently vulnerable. The more generations
of a pest in a season, and the longer the pest is subject to
selection pressure from a single tactic, the greater the odds
the pest will adapt around the tactic and adapt quickly.”
Charles M. Benbrook, PhD.
When Bt-transgenic crops were introduced, Monsanto admitted that
resistance was a possibility, but unlikely if a 5 percent “buffer zone” of
traditional plants was planted as well. Then the following discoveries were
made:
 Bt endotoxin expression under field conditions is not uniform, providing
some insects with a chance to avoid plant tissues delivering a lethal dose.
 Resistance gene to Bt endotoxin appears to be a dominant trait.
 Bt-corn can adversely impact populations of key beneficial insects.
 Resistance to Bt is not as rare as previously suspected.
Since the release of these studies, Monsanto increased the necessary safe buffer
zone to 50 percent.
Antibiotic Gene Markers
 AGM are used to identify transferred cells within the
DNA, but many worry that the genes could inadvertently
be transferred to humans, decreasing the effectiveness of
some antibiotics.
Scientific studies show that this is an “unlikely,” but
possible scenario, so...
The genes chosen confer resistance to a narrow range of
specific antibiotics no longer considered important for
medical treatment. And...
The FDA has suggested that biotech companies find
alternatives to antibiotic resistance genes.
Allergies!?...
The National Academy of Sciences has said that GM food might
cause allergic reactions, some serious, even life-threatening.
Physicians are not required to report allergic reactions observed in
patients, and there is no existing registry to record such data.
Therefore, without data being collected and analyzed, stable
conclusions regarding the existence or possibility of new allergens
cannot be made.
Current testing for allergenicity often compares the new protein with
known allergens such as wheat, peanuts, milk, eggs, and crustaceans.
In 1992, the United Nations met in Rio de Janerio for the
Conference on Environment and Development. The
subsequent declaration contained the following statement.
Principle 15 In order to protect the environment, the
precautionary approach will be widely applied by States
according to their capabilities. Where there are threats of
serious or irreversible damage, lack of full scientific certainty
shall not be used as a reason for postponing cost-effective
measures to prevent environmental degradation.
In short, follow the precautionary principle...
US and EU
U.S. government agencies take a “risk-based” approach to
regulating biotechnology. That is, they focus on the end
product, and its risks, instead of the process by which it was
created.
In contrast, the EU considers GMOs to be special category of
organism. A quote from the Commission of European
Communities Directive on the Deliberate Release to the
Environment of Genetically Modified Organisms reads,
“It is evident that a case-by-case examination and an
environmental risk assessment is appropriate for the use of
genetically modified organisms.”
Why has regulation proved so difficult?
• The process of policy cannot keep up with the
pace of science.
• The pro-business approach of U.S. regulatory
agencies often conflicts with consumer sentiments.
— “I have studied the linkages between technology, policy,
economics and the environment during most of my career. It is clear
to me that the role of traditional farm policy is greatly diminished,
that the private sector now largely controls the selection of
technologies that are reaching farmers, and that the discipline of the
open market is being undermined by industry consolidation.”
Charles M. Benbrook, PhD.
• Disregard for the precautionary principle by
corporations, scientists, and regulators.
• A national myopia that trades possible ecological
problems for quick business profits.
The science of biotechnology holds great possibilities
that should be explored for the future. It should also
be recognized, however, that biotechnology is an area
of science not fully experienced by nature. Any science
concerning the release of “human invention” into the
environment, especially if intended for consumption,
should be put to the most rigorous testing.
“I hope I’ve persuaded you that this particular
challenge is complex, tricky, difficult, and that solving
it will require much more than straightforward risk
assessment or cost benefit analysis, and certainly
more than…rhetorical admonitions that it’s not nice
to fool with Mother Nature.” Dr. Donald Kennedy, president
of Stanford University; 1992