Sarah Bastarache LS 479 Term Paper Genetic Modification ...

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Sarah Bastarache

LS 479 Term Paper

Genetic Modification: Solution or Setback?

The Controversy Over Transgenic Technology

Throughout history, technological innovation has been a subject of intense debate.
Revolutionary ideas have dramatically changed the
lives of human beings in nearly every aspect
of life, from birth to death. We have built massive cities, paved millions of miles of roads, and
expanded our real m of exploration beyond the Earth’s atmosphere. Many inventions have
seemed, at first glance,
to offer only positive results, but as the years pass, the repercussions of
our technol ogical boom are becoming more and more apparent. The automobiles that were
once so celebrated have become a large source of pollution that many argue is dramatically
ch
anging the world’s climate. Manmade materials, which have allowed us to create
uncountable numbers of products, are filling up our landfills, and the natural resources we use
to support our luxurious lifestyles are rapidly depleting. As we search for new

technologies to
solve the problems we have created for ourselves, new debates have begun to form, both
scientific and ethical, over the extent to which humans should be able to manipulate the world
around us. The subject of
genetic engineering is at the
center of these debates, and over the
past decade has developed into a worl dwide controversy. Genetic modification spans all
subject areas, from economics to medicine to agriculture, and yet its omnipresence has not
made it any less disputable. What us i
t about this technology that makes it so questionable,
both scientifically and ethically? Should genetic engineering be the solution to problems we
face now and in the future? The answers to these questions are unclear, and one can only begin

to develop a

viable response after a thorough examination of both the current and potential
future roles of genetic modification in the world today. This paper provides a basic overview of
the present state of transgene research, and takes a closer look at the area o
f biotech crops,
specifically

the drought
-
resistant variety of rice that is
currently being considered as a potential
solution to the effects of climate change on China’s rice production.


Biotechnology, (the use or alteration of other
living things in p
rocesses that benefit
humankind), has been around for at least 10,000 years, ever since humans began raising crops
and domesticating animals. Our ancestors, in choosing to sow seeds from the most successful
crops lines and breed only the strongest cattle,

were unknowingly altering the genes of these
organisms for human benefit. Cloning became popular when we discovered we could breed
plants from cuttings (the word ‘twig’ translates to
clone
in Greek). Wine, bread, beer, and
cheese
-
making all required the

manipulation of microorganisms. However, it is only after we
discovered the science behind t
hese processes, the key to life,

DNA and its components, that
genetic engineering was born. Defined as the direct alteration of genes or transfer of genes
from on
e type of organism to another, genetic engineering first appeared in the early 1970’s in
the lab of Paul Berg, a chemist at Stanford University. He was able to successfully splice a gene
from SV40 (Simian Virus 40
-
a monkey virus that has been shown to cau
se cancer in mice) into
the genome of a lamda virus. This was the first known production of recombinant DNA, or DNA
in which DNA from another type of organism has been introduced (Yount 4
-
9). Within the next
several years, this process was modified and i
mproved. Viruses were soon being used to insert
foreign genes into bacteria, plants, and animals.



Today manipulation of recombinant DNA can be found in numerous labs around the
worl d. Transgenic microbes are especially common, particularly in the medic
al industry. Insulin
was the first human hormone to be produced commercially by transgenic organisms, through
the insertion of the human insulin gene into bacteria. The human growth hormone (hGH) soon
followed, a drug that has been shown to help treat h
yperpituitarism and other types of
pituitary disease in children, (although it is better known for its role in promoting muscle
growth and improved physical performance in athletes) . Other drugs developed through
transgenic microbes include fertility dru
gs, medication for bleeding disorders, renal failure, and
heart disease, as well as those used to help manage diseases like leukemia, hepatitis, and
multiple sclerosis (Avise 16
-
19). Supporters of this technology argue that using bacteria as
‘factories’ f
or drugs allows much easier and cheaper production of medication, and in some
cases seems to be safer for patients than the ‘natural’ sources. Early production of hGH, for
example, was achieved through the collection of the hormone from the pituitary glan
ds of
human cadavers. Not only was it difficult to obtain these sources, but it was later discovered
that some of the donor’s brains carried Creutzfeldt
-
Jakob disease (CJD or mad
-
cow disease).
The purification process of the hormone had not fully removed

the disease and at least one
child was shown to have died from contracting CJD through hHG treatments (Avise 20). Even
though transgenic technology has proven safer than traditi onal methods in some respects,
enzymes produced through biotech organisms hav
e been on the market for less than 20 years,
and so long
-
term health effects are still unknown. Despite this argument, numerous other
industries utilize transgenic microbes, with approximately 200 microbial biotech enzymes found
in the commercial marketpl
ace. Used in everything from food processing to the production of

paper, cleaning products and textiles, biotech microbes are the focus of intense research.
Supporters of transgenic organisms foresee enormous possibility in this area, particularly
consid
ering that less than 1% of the world’s microbes have even been identified (Avise 23
-
25).



Other developments in GE technology include research with GE animals. Much like with
microbes, genes are introduced into animals in order to quickly and easily prod
uce different
products, including medicines. The first drug produced by a transgenic animal to be approved
by the European Medicines Association was an anti
-
clotting protein, ATryn, secreted in the milk
of a goat in Massachusetts named Sweetheart. The pr
ocess to obtain ATryn involves traditional
milking of the animal, followed by purification and drying of the protein. It is estimated that
costs in production of Trypn could be up to 100 times less than traditional cell
-
culture methods.
However, research

with transgenic animals is expen
sive, and numerous other
trials with farm
animal pharmaceuticals (now referred to as ‘pharming’) have not been as successful (Ledford 1
-
2). Another experi ment that made it into the mainstream media was the insertion of
spider
-
silk genes into mammals
-
specifically cows and pigs. The mammals were shown to successfully
secrete silk proteins out through their milk. Scientists hope this research might lead to low
-
cost
production of these flexible, ultra
-
strong fibers, whose
potential uses include artificial t
endons
and ligaments, biodegrad
able sutures, and ‘green,’ eco
-
friendly fishing lines, (which would
degrade in about a year compared to current fishing lines that tend to accumulate in aquatic
environments) (Avise 78
-
80).


Animals are not only being used as producers. Some scientists, in response to the
negative impact of phosphorous
-
containing hog waste on the environment, have designed

‘environmentally
-
friendly’ pigs. Phosphorous is a nutrient pigs should obtain natura
lly through
consuming germinated plants. Hog farms, however, feed with corn seed, which has about 70%
of its phosphorous locked up as phytate, a substance which the simple stomachs of hogs (and
chickens) are unable to digest. This means the phytate passe
s out of the hogs into the
environment, where it becomes the environmental pollutant, phosphorous. The hogs, in the
meanti me, must be given phosphate supplement
s in order to prevent dietary de
ficiencies.
These biotech pigs have a gene that codes for the
protein phytase, which breaks up the phytate
in corn seed. Phytase is secreted in the saliva, resulting in pigs with 75% less fecal phosphorous
than non
-
GM ani mals (Avise 80
-
82). Despite these results, many argue that the real solution to
environmental
problems caused by hog waste is to rethink the design of large
-
scale farms.

Another popular use of GE animals is for research, particularly on mice. Scientists now
have the knowledge to insert and delete spec
ific genes into mice embryos. The s
tudy of th
e
develop
ment of these GE mice allow
scientists to determine the function of the gene in
question. Other uses of GE lab animals include medical research that involves intentionally
inserting genes that cause disease, such as diabetes or cancer, into the a
nimals, and using the
resulting infected organism for testing of experimental treatments. The use of GE animals in
the laboratory has more than quadrupled in the last 10 years, and does not appear to be
slowing (Rincon). Use of animals in any type o
f
exp
erimental studies, be they for production,
environmental, or medical purposes obviously brings up serious ethical and animal rights
issues, but the prevalence of GE animal studies have shown that, at least for now, animal rights
laws are not stringent enou
gh
to
override the demands of the scientific community.


Perhaps one of the most commercialized areas of genetic modification is that of GM
crops. It is estimated that 80% of processed food in the United States comes from GE crops,
with 252 million acres

grown worldwide (Lemaux 777).
Although much of our food contains
GM ingredients, few whole GM foods (or living modified organisms
-
LMOs) are commercially
available in the United States. Only GE squash, corn and papaya can be found on the shelves
(Lemaux
777).
The traits found
in non
-
commercialized transgenic
crops
, however,

are as
diverse as those of GE animals.
Experimental GE crops of mustard, cotton, and corn have been
engineered to create the first ever plant
-
synthesized plastic compounds. These ‘
bioplastics’ are
renewable and biodegradable. However, scientists have yet to produce a plant that produces
usable amounts of the plastic fibers, and it is thought that the plants may be adversely affected
by a significant increase in plastic content (Avi
se 67). Other innovati ons include potatoes that
are 60% starchier than traditional crops so that they absorb less fat during frying, citrus fruits
with reduced liminoid compounds for decreased bitterness, soybeans with less saturated fat,
peanuts with lon
ger shelf lives, and even experimental crops of beans engineered to eliminate
the common side effect of post
-
consumption flatulence (Avise 70)!

GE crop research goes beyond traits engineered for pure human convenience, with a
large area in GE research no
w focusing on medical and pharmaceutical producti on.
One of the
first medically significant GE plants was produced in 1997 when the gene coding for human
hemoglobin was isolated and place
d in bacteria. The bacteria were

then transferred to tobacco
plants,

creating a GE crop that manufactured significant amounts of human hemoglobin. This
was exciting for scientists as it opened of a whole new area of genetic modification, and created
the potential for an alternative source of critical blood components. Th
e hemoglobin produced

by the GE tobacco was thought to be safer than traditional blood supplies, which can carry
diseases (Avise 61
-
62).
Vaccine production has also become a major focus in GE crop research.
Maize, potato, rice, soybeans, and tomatoes hav
e all been used to produce vaccines for both
humans and animals. These vaccines, which would be affective through consumpti on of the
plant, include a potato
-
based vaccine for hepatitis B, a subunit vaccine for pneumonic and
bubonic plague, a pollen vaccin
e that reduces allergy symptoms, and a rice vaccine that targets
asthma and dermatitis (Lemaux 789).

The potato
-
hepatitis vaccine has been reported to have
successfully been tested on humans, with 60% of volunteers showing increased immunity
(equivalent t
o a standard vaccination), after consuming a single, 4 ounce serving of transgenic
potatoes (Thomson 129).

Other research has focused on non
-
edible vaccine plants, such as
tobacco. It has been found that, when expressed in the chloroplast, enough anthrax

vaccine
could be produced in one acre of tobacco to inoculate the entire population of the United
States (Thompson 126). Scientists that support the development of GE plant pharmaceuticals
argue that vaccines in plant form would be easy and inexpensive t
o distribute to developing
countries, given that they would need limited or no processing and do not need to be kept cold
to remain effective. However, there is a viable concern that pharmaceutical crops could
contami nate food sources, and stringent regul
ations have been put in place for every step of GE
pharmaceutical plant growth. The risk of gene flow that is thought to be associated with the
cultivation of GE pharmaceutical plants may be distressing enough to keep these crops from
becoming as widespre
ad as other, seemingly less threatening GE varieties.

Although a large amount of research does go in to other areas of GE crop research, the
majority of GE crops grown today are those that have been engineered for resistance to outside

forces, such as pest
s, herbicides, fungus, and drought (Brooks 3). A report came out in 2006
that examined the global impact of bi otech crops over the previous 10 years. It concluded that
through the use of GE crops, farm i ncome had increased by $27 billion. Pesticide spra
ying had
decreased by 224 million kg, and carbon emissions had been reduced by 9 million kg, (or the
equivalent of removing 4 million cars from the road for a year)(Brooks 139). The United States
grows most of these crops, with 87% of US soybean crops bei
ng herbicide
-
tolerant (HT), 60% of
total cotton crops being HT, and 52% of corn being pest
-
resistant (Lemaux 777). Pest
-
tolerant
plants contain genes for Bt toxins, which are derived from the insect pathogenic bacteri um
Bacillus thuringiensus.
Bt toxins w
ere first used as a biodegradable pesticide, and

are still the
worl d’s leading biopesticide, making up 90% of biopesticide sales. The Bt toxin binds to
glycoprotei n receptors in the midgut of lepidopteran insects, ultimately causing gut paralysis
and even
tual starvation or sepsis (Hilder 179). The pesticide has been utilized for approximately
40 years to control lepidopteran pests, and in the early 1980’s the genes of the toxin were
successfully cloned and expressed in tobacco and tomato plants (Moose 969
-
970). These were
the first pesticide
-
resistant GM plants, and they paved the way for the modification of
numerous other Bt plant varieties, including cotton, rice, potatoes, brinjal, maize, broccoli,
oilseed rape, soybeans, walnut, larch, poplars, sugarca
ne, apples, peanuts, chickpeas, and
alfalfa (Hilder 179).

Herbicide
-
tolerant plants include Round
-
up Ready varieties, which have been made
resistant to the broad
-
spectrum herbicide, glyphosate, by the addition of a bacterium
-
derived
gene that codes for a

glyphosate
-
resistant protein (Wagner 155
-
156). Glyphosate is typically
applied prior to planting, but with Round
-
up Ready plants, the herbicide can be sprayed after

planting, which means easier weed control. Glyphosate is a milder pesticide than many of

the
traditional pesticides that farmers use on non
-
GM crops, and farmers find they do not need to
spray Round
-
up Ready crops as often as traditional crops to maintain weed control. Easier
weed management has led to an increase in reduced and no
-
till prac
tices, which decreases
overall costs for farmers as well as helps to better preserve nutrients in the soil (Thomson 41).
The adaption of Round
-
up Ready has allowed one
-
thi rd of US soybean farmers to employ no
-
till
practices, and has increased profit from
soybean crops worl dwide by nearly 10% (Rauch 145,
Thomson 41).

Papaya is a crop that has been drastically affected by GE technology, particularly in
Hawaii, where Papaya crops make up a large part of the state’s agricultural industry (Thomson
54). GE pa
payas have been engineered to resist the
Papaya Ringspot Virus
(PRSV), a pathogen
spread by aphids which compromises the photosynthetic abilities of papaya foliage. Infection
results in stunted growth, poor fruit quality, and eventual death of the tree. T
he virus has
wreaked havoc on traditional Hawaiian Papaya crops since 1950’s, and would have ruined the
entire industry if not for the introducti on of GE crops in 1998. Within the first year of
availability, 98% of Hawaiian papaya farmers had signed up to

receive the seed and 73% were
growing it (Davisdson 487
-
488). Acceptance of GE papaya by growers, packers, and consumers
led to a quick recovery of the Hawaiian papaya industry, which many claim was ‘spared from
disaster’ (Gonsalves 38
-
39).

Obviously not

all GE technology is met with the acceptance that the Hawaiian Papaya
industry demonstrated, and for good reason. Genetic modification is such a controversial topic

because of the risks it presents, both scientific and ethical. Scientifically, the short
-
term effects
of GE technology, specifically in the crop industry, tend to be economically and environmentally
positive. Critics, however, argue that in the long
-
term, gene manipulation could have dire
consequences for humans and our environment. One of
the greatest concerns is gene flow to
non
-
GE organisms. Although studies have shown that gene flow between GE crops and the
environment tends to be very li mited, it has been proven that gene flow does occur.
Researchers in Mexico recently confirmed that
GE corn is currently growing in fields where only
traditional corn crops should be, and studies on GM rice show that low frequencies of gene
flow to weedy relatives will occur if the species are located close enough to each other (Dalton
149, Bao
-
Rong 677)
. Scientists have made an enormous amount of progress in the
understanding of genetics, inheritance, and gene expression, but a great deal is still unknown.
Scientists have no idea how the introduction of GM DNA, such as that of pharmaceutical
-
producing
organisms or bioplastic cotton, into wild ecosystems might affect the biodiversity
and overall ecology of natural habitats. The creation of ‘superweeds’ is a major worry among
scientists. If GM traits such as an herbicide
-
resistance or Bt gene were to tr
ansfer over into
weed species, the result could lead to major invasive behavior, causing significant losses in
biodiversity as well as crop output (Altieri 41
-
42). Even without gene transfer, the promotion of
GE crops further encourages the development of

monoculture crops, which in and of
themselves limit the biodiversity in agricultural regions (Avise 73).

Worries are also found among those interested in human health. Although the
nutritional content of GE foods sold commercially is thoroughly teste
d before release for
human consumption, there are hidden risks and potential concerns over transgenic foods. The

introducti on of allergens into GE crops is one viable problem. An example of this occurred
when scientists tried to increase the amino acid c
ontent of the soybean by introducing a
protein derived from Brazil nuts. The operation was halted when testing showed that people
with Brazil nut allergies had similar reactions to the GM soybean (Lemaux 786). Although
testing caught allergen hazards in
this case, if GM crops with allergens were to unknowingly mix
with traditional crops, products without proper allergy labels could make their way into the
food supply. Another concern is the introduction of unwanted genetic information into human
bodies t
hrough consumption of GE foods. Plasmids containing antibiotic resistant strains of
DNA are often used in GE technology. Although DNA in food is easily broken down by enzymes
in saliva, some studies show that gut bacteria can take up plasmids and genes
that have not
been digested. This creates the potential for the spread of anti biotic resistance (Altieri 30).
GM foods have been consumed by the public for over 20 years now with no obvi ous adverse
effects, but only time will tell if this technology wil
l cause any long
-
term health effects for
consumers.

Scientists debate over the health and environmental effects of GE organisms, but surely
the largest controversy over transgene research has to do with ethics. Genetic modification has
been able to spre
ad all over the world i n the past few decades because science has yet to find
any solid evidence that it does any significant damage to humans or the environment. Most
foods containing GM ingredients are not labeled because physically researchers have pro
ven
them to be no different nutrition
-
wise than non
-
gm ingredients. A problem arises, though,
when personal choice comes into play. Some people, despite the fact that they are told GE
foods are safe, still do not want to consume them or support their pro
duction purely based on

their own personal belief systems. Many see the manipulation of genetic material as scientists
‘playing God,’ and therefore find it unethical to participate in the process. This attitude of
morals versus science is most obvious whe
n the question of animal rights comes up. It may be
perfectly safe, and even beneficial, for humans to introduce disease
-
causing genes into test
mice. However, many would argue it should not be done purely on the basis that animals must
suffer unnecessar
ily during the process. Whatever area of transgenic discovery is in question,
there is always an argument to bring morals into the picture. Skeptics of genetic modification
argue that scientists who push for further introduction of GE technology to consum
ers must
begin to start recognizing that personal beliefs of individuals must be given the same weight as
scientific research if any resolutions are to be reached (Myskja 225).

A good example of the conflicting sides of the genetic modification debate can

be seen
in the case of the introduction of drought
-
resistant rice to the poorer areas of Asia. Drought is
a major constraint of rice production in Asia, especially recently with the changing climate. It is
estimated that one
-
third of the total rice crop
s in Asia are subject to drought stress, with losses
affecting the poorest farmers most dramatically (Venuprasad 232). Scientists working with
GM crops recently inserted the
Arabidopsis HARDY

(HRD) gene into rice plants. This gene
proved to create dro
ught
-
tolerance and salt
-
tolerance in the plants by improving water use
efficiency
-

the ratio of bi omass produced to water used. The resulting plants have

increased
root strength and leaf biomass to enhance photosynthetic assimilation and reduce
transporat
ion (Karaba 15270). Supporters argue that this technology could be a huge benefit to
struggling rice farmers, increasing yields and decreasing the amount of water needed for the
cultivation of healthy crops. Opponents argue that GE technology is expensiv
e and risky. Seeds

are more expensive than traditional crops, and only large, private companies that can afford
the research trials are able to obtain the patents to produce them. This means that small
farmers either never actually get access to GE techn
ology, or they end up in the pockets of large
corporations (Heintzman 112). Some are for using our knowledge of genetics to find intragenic
varieties of drought
-
tolerant crops, seeing this technology as less of a risk than transgenic
research (Venuprasad
242
-
243). Still others state that

promoting GE crops would be a blatant
misuse of the land and promote mass, unsustainable monocul ture crops. They argue that the
Asian people have successfully used their own selection techniques for centuries in order to

adjust for changes in weather patterns and that the focus should be on increased education
relating to traditional rice cultivation (Bray, 19
-
26).

This debate involves scientific, economic, environmental, and ethical issues, and I am
not sure there is a

clear answer about what di rection to take in this case or any other where GE
technology is concerned. I do think that research has shown we have the potential to do
beneficial things with GE technology. With our changing climate and rapidly growing
popul
ation, we are going to have to find viable solutions to issues like world food and resource
shortages. Although some aspects of GE technology seem like they may be helpful, I am
hesitant to fully support the majority of research currently underway. Transg
enic research is
advancing at alarming rates and I worry about our judgment in how far we should go with this
knowledge, as well as the direction we are heading.
Cradle to Cradle
brought to my attention
the fact that just reducing our impact on the enviro
nment is not going to solve our problems in
the long run. If we do proceed with GE technology, it needs to coincide with sustainable
practices instead of promoting monoculture farmi ng. We need to stop using technology for

quick
-
fixes and start integratin
g it into more sensible, long
-
term solutions. I have noticed that
an overwhelming viewpoint among scientists, ethicists, and economists alike is that there is no
one answer to our global problems. In order to improve the lives of those being hit hardest
,
specifically people living in developing nations, we need to work on their whole infrastructures.
Education systems need to be built up, so that people can become aware of the technology that
is available to them and make educated decisions on how to ut
ilize it. More considerations
need to be taken on how to use the land in sustainable ways, which should allow struggling
economies to get back on track. Despite the apparent potential that GE technology has to
improve our lives, it should never be seen a
s the final solution to any issue. The development
of stronger and more diverse agricultural, economic, and intellectual infrastructures must also
be employed to see any truly sustainable improvements in the lives of people today.



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