Genetically Engineered Foods
The use of genetically engineering in agriculture and food production has
an
impact, not only on the environment and biodiversity, but also on human
health.
Therefore, thorough biosafety assessment requires, not only an
evaluation of
environmental impacts of genetically engineered organisms, but
also an
assessment of the risks that genetically engineered food pose for the
health of
consumers. Let us take deeper look at some of the aspects related
to genetically
engineered foods. What is Genetic Engineering? Genetic
engineering is a
laboratory technique used by scientists to change the DNA of
living organisms.
DNA is the blueprint for the individuality of an
organism. The organism relies
upon the information stored in tits DNA for the
management of every biochemical
process. The life, growth and unique features
of the organism depend on its DNA.
The segments of DNA, which have been
associated with specific features or
functions of an organism, are called
genes. Molecular biologists have discovered
many enzymes, which change the
structure of DNA in living organisms. Some of
these enzymes can cut and join
strands of DNA. Using such enzymes, scientists
learned to cut specific genes
from DNA and to build customized DNA using these
genes. They also learned
about vectors, strands of DNA like viruses, which can
infect a cell and
insert themselves into its DNA. Scientists started to build
vectors, which
incorporated genes of their choosing and used vectors to insert
these genes
into the DNA of living organisms. Genetic engineers believe that
they can
improve the foods we eat by doing this. At first glance, this might
look
exciting to some people. Deeper consideration reveals some advantages
and
serious dangers. What are the advantages of Genetically Engineered Food?
Genetic
engineering gives today’s researchers considerable advantages in
plant
breeding programs. · Predictability Scientist can identify the specific
gene
for a given trait, make a copy of that gene for insertion into a plant,
and be
certain that only the new gene is added to the plant. This eliminates
the"backcrossing", traditional plant breeders must do to eliminate
extraneous
undesired genes that are frequently introduced when using
cross-hybridization.
· Significant acceleration of the development timetable.
New technique takes
about 5 years to remove the undesirable traits compared
to 12 years of process
with the traditional techniques. Plant breeders do not
use recombinant DNA
techniques exclusively. Instead they use a combination of
new and traditional
methods to provide a plant with quality, yield, weather
and pest resistance and
other desirable traits. · Improved quality with more
choices for the customers.
Genetically engineered food especially fruits
and vegetables allow to have
plenty of time for shipping and sale and it
helps to keep the them stay ripe
without getting rotten. Some of the fruits
and vegetables need warm climates to
grow, so most off-season store them must
travel a long way after they are
picked. One example is the Flavr Savr
tomatoes. To survive their journey intact,
tomatoes are picked while they are
green, which is a food which is a good way to
avoid bruising, but which
results in a tomato that is often described as having
the consistency and
mouth-feel of a tennis ball. In the case of Flavr Savr
tomatoes, the company
solved the rotting problem by inserting a reversed copy-
an "antisense" gene
of the gene that encodes the enzyme that results in
tomato spoilage. This
suppresses the enzyme that results in rotting, allowing
the tomato to stay
ripe, but not rot, up to 10 days—plenty of time for
shipping and sale.
Refrigeration is not necessary. What are the dangers of
Genetically
Engineered Food? · Is it safe to eat? There has been no adequate
testing to
ensure that extracting genes that perform an apparently useful
function as
part of that plant or animal is going to have the same effects if
inserted
into a totally unrelated species. To consumers, most genetically
engineered
foods are essentially foods with added substances, usually proteins.
This
is because genes are "translated" into proteins by cells. Therefore,
when a
genetic engineer adds, say, a bacterial gene to a tomato, he or she
is
essentially adding a bacterial protein to that tomato. In most cases these
added
proteins would likely prove safe for human consumption. Nevertheless,
just as
with conventional food additives, substances added to foods via
genetic
engineering may in some instances prove hazardous. Unfortunately,
food allergies
are poorly understood, and in many cases scientists will not
be able to test
potential allergenicity of genetically engineered foods. Even
if there was some
testing, the long term affects to humans, animals, and the
environment from
these modified genes "escaping" and mixing with unmodified
ones are unknown.
· Health Hazards There are several differences between the
normal breeding
process and the artificial genetic manipulation process. One
key difference is
the use of highly infectious viruses for artificial genetic
manipulation as a
promoter to witch on the introduced gene. Some of the
viruses used are highly
infectious. Genetic manipulation can increase the
risk that the plant will
develop toxic or allergy-causing compounds. Another
possibility is that regulate
exposure to foreign DNA and RNA material
inserted into these artificial foods
could cause allergic reactions or
autoimmune disease. Allergens A number of
molecular mechanisms have also been
identified through which the genetic
manipulation of food producing organisms
could generate new allergens or
increase the allergenicity of proteins
normally present in food producing
organisms. Because allergen-carrying
transgenic foods will in most cases
maintain the appearance of their natural,
non-allergenic counterparts, they pose
a serious hazard to the consumer.
Consumer will not be able to avoid these
allergenic foods, because they will
not be able to distinguish them from the
corresponding natural foods. The
labeling of all genetically engineered foods
would, of course, solve this
problem and would also make it possible for health
authorities to trace
allergen problem that arise. Toxins & Poisons In
addition to
allergenicity, recombinant proteins could manifest a variety of
other
biological activities, and in the case of recombinant enzymes, could
catalyze
the production of other compounds with biologic activities not
normally
present in a particular food. For instance such substances could act
as toxins
or irritants and could act at the biochemical, cellular, tissue or
organ levels
to disrupt a range of physiological functions. An example of a
class of
genetically engineered foods that are of particular concern are
those that have
been modified to produce biological control agents such as
the family of
insecticidal Bt enterotoxins. The Bt toxin, which has been used
topically in
organic farming, has powerful biological activity. If consumed
in larger amounts
it can become a toxin. Plants genetically-manipulated to
produce Bt toxin
produce at least 1000 times more Bt toxin per acre than does
a heavy application
of Bt directly on plants. There was another case where
one company genetically
engineered a microorganism to produce L-tryptophan at
high levels killed almost
37 people and made 1500 permanently disabled by
using that product. This was due
to the presence of traces of a toxic
contaminant. This contaminant was extremely
powerful. Damage to Nutrition
quality A 1999 study by Dr. Marc Lappe published
in the Journal of Medicinal
Food found that concentrations of beneficial
phytoestrogen compounds thought
to protect against heart disease and cancer were
lower in genetically
modified soybeans than in traditional strains. These and
other studies,
including Dr. Pusztai’s, indicate that genetically engineered
food will
likely result in foods lower in quality and nutrition. For example the
milk
from cows injected with rBGH contains higher levels of pus, bacteria,
and
fat. Sources of risk Unmodified Organism (UMO) The genetic engineering of
foods
involves the introduction of new genetic information into a
food-producing
organism. Some of the health risks associated with genetically
engineered foods
can be anticipated on the basis of what we already know
about the
characteristics of the organism in its unmodified state (called the
unmodified
organism UMO) from which the genetically engineered organism is to
be generated.
Gene Source (GS) Other aspects of the risk associated with
genetically
engineered foods can be deduced from the characteristic of the
organism that is
the source of the genetic information introduced into the
food producing
organism (called the gene source or GS). For instance, if a
gene derived from
peanuts is introduced into a tomato, food produced from the
resulting
genetically engineered tomato might cause allergic reactions in
people that are
allergic to tomatoes (the unmodified organism) or to peanuts
(the gene source).
Procedure of Genetic Engineering In addition to UMO
and GS, there is another
source of potential risks, which is the procedure of
genetic engineering itself.
Current recombinant DNA methods and those
likely to be developed in the future
are all capable of accidentally
introducing unintended changes in the function
and structure of the
food-producing organism. As a result, the genetically
engineered food may
have characteristics that were not intended by the genetic
engineer, and that
cannot be foreseen on the basis of the known characteristics
of the
unmodified organism or gene source. Labeling Issues FDA requires labeling
of
genetically engineered foods under certain exceptional circumstances.
Since
most genetically engineered foods will be indistinguishable in
appearance from
non-engineered foods, consumers will generally not know what
they are buying.
FDA ignores consumers’ right to know by ignoring
longstanding regulations that
require in most circumstances that manufactures
label foods to disclose their
ingredients. For example, researchers have
genetically engineered vegetables to
produce a new protein sweetener.
Existing FDA regulations mandate that companies
disclose sweeteners added to
canned vegetables via conventional means. Yet, FDA
will not require that
proteins sweeteners added to vegetables via genetic
engineering be labeled as
ingredients. Labeling is vital to food allergic
individuals, who need to know
when their purchases are potentially allergenic.
FDA will require
labeling of foods genetically engineered to contain potential
allergens from
only the most commonly allergenic foods—a requirement that
threatens
individuals with less common food allergies. FDA also will require
labeling
if a company uses genetic engineering techniques to change a
food’s
composition significantly. For example, when one manufacturer modified
canola to
produce increased levels of lauric and myristic acids in the seed
oil, FDA
agreed that the common or usual name for this oil would be "laurate
canola
oil" in order to distinguish it from traditional canola oil. Some
vegetarians
and individuals who follow religious dietary laws have told FDA
that they want
to know when animal genes are added to plants used as foods.
FDA has taken no
steps to accommodate their dietary beliefs and restrictions.
What can you do as
a consumer ? Look for soy products and ingredients like
tofu, tempeh, miso, soy
sauce, soymilk that are organic. All other soy
ingredients are almost
genetically manipulated and herbicide- treated. The
same is true for canola,
corn, dairy products and potatoes. Look for organic
corn, potato and dairy
ingredients when you shop. It may be best to avoid
canola altogether because it
is rarely organic and is usually chemically
treated. A recent experiment
conducted by independent expert DR. Alpad
Puszatai in the United Kingdom has
shown that genetically manipulated foods
can, when fed to animals in reasonable
amounts, cause very gradual organ
damage and immune system damage. Conclusion
Reading the label is an
important part of shopping for a consumer. If consumers
do not want to
consume genetically manipulated foods, they can always contact
the store
managers and ask them to carry more organic foods in the store. Most
of the
time the food product manufacturers also pay attention to consumers
feed
back. Further, if one has questions or concerns about such issues, one
can
always contact a nutritionist who is aware and well informed of the pros
and
cons of Genetically Engineered
Foods.
Bibliography
Bindslev-Jensen, C. (1998). Allergy risks of
genetically engineered foods.
Allergy 53: 58-61. Cummins, R. &
Lilliston, B. News and Analysis on Genetic
Engineering, Factory Farming
& Organics. http://www.purefood.org/ge/cfs20.cfm
Cummins, R. Hazards
of Genetically Engineered Foods and Crops: Why we need a
Global
Moratorium. http://www.organicconsumers.org Fagan, J.B. Assessing
the
Safety and Nutritional Quality of Genetically Engineered Foods.
http://www.netlink.de/gen/jfassess.htm
Malcom, A. D. (1999). Health Risks
of Genetically Modified Foods. Lancet 354:
69-72.