Humboldt
County Ballot Initiative to Ban Genetically Modified Organisms
Mark
S. Wilson, Humboldt State University, Department of Biology
Examples of GMOs
Insulin-producing
bacteria
The first commercial GMO, created
in 1978 at UC San Francisco, was a bacterium that produces human insulin. Insulin is a protein hormone that
regulates the concentration of glucose in the blood. Humans with diabetes
cannot produce insulin normally, and therefore need to rely on an outside
source of this hormone to maintain normal glucose levels. In the 1920s, people
started isolating insulin from cows and pigs to treat human diabetes, but there
were problems related to the safety, purity, reliability, and amount of insulin
that could be obtained in this way.
Because of this GMO, diabetics today are assured of a reliable and
inexpensive supply of insulin. A
number of other medically-important proteins are now produced by similar GMOs.
Vaccine-producing
microorganisms
A number of recombinant
(transgenic/GMO) vaccines are now produced and used. One example is a
recombinant vaccine that confers protection against Hepatitis B virus. The
viral gene for production of a surface protein was inserted into a strain of
yeast, which produces the protein in large quantity. Purified protein can be injected intramuscularly to initiate
the development of protective antibodies. This vaccine, approved for use since
1986, is promoted
by the World Health Organization as a safe and effective tool in the
prevention of hepatitis B infections, which kill more than 1 million people
annually. More than 116 countries
include this vaccine in their routine immunization routines. Numerous other
vaccines are made in this fashion, replacing blood-derived vaccines and more
dangerous live attenuated viral vaccines.
Corn/Soybeans/Canola/Cotton
The most common crop GMOs
are plants that have been modified in some way to make them easier for farmers
to grow. Unlike with
insulin-producing bacteria, the goal of these modifications is not to create a
product that is better for the consumer, just for the farmer. These include crops that produce bacterial proteins
that are toxic to insect larvae and thus, at least theoretically, reduce the
need for expensive and dangerous applications of insecticides. They also include crops that can
withstand herbicide applications (i.e. Roundup-Ready crops).
These products are the ones
that have caused the most controversy to date. Some of the factors contributing
to the controversy are that there is no health benefit for the consumers of
these products, they are grown in large quantity, and people tend to consume a
lot of these foods. The manufacturers would probably claim that these crops are
cheaper to produce, and that is an economic benefit for the consumer. Additionally,
farmers are able to reduce applications of dangerous chemicals, and switch to
less toxic chemicals, which in theory provides a universal benefit. The
environmental costs/benefits of these crops are hard to calculate, but some
farmers have chosen these crops because they are more compatible with no-till
and low-till approaches that reduce loss of topsoil.
More recent modifications
have focused on consumer health benefits rather than benefits for the farmers.
For example, researchers at UC Berkeley are working to lower
or eliminate allergy-causing proteins from common foods such as mlk and wheat.
Hypoallergenic soybeans
have also been developed. Other varieties of soybeans have been modified to be
lower in linoleic acids, which will reduce the amount of hydrogenated fats in
soy-based margarine and shortening. Hydrogenated fats reduce the level of HDL
(good cholesterol) in humans, while raising the overall cholesterol
levels. Hydrogenated fats thus
increase the risk for heart disease. Other modifications for consumer benefit
include soybeans higher in monounsaturated fats and omega-3 fatty acids, which
may help reduce the risk of heart disease.
Golden Rice
Golden Rice is a transgenic
rice that has been modified to produce beta-carotene, which humans can convert
to Vitamin A. Golden rice is to be distributed free to farmers in the
developing world in the hopes of alleviating Vitamin A deficiency, which is
implicated in more than one million deaths and 350,000 cases of childhood
blindness each year. Because
Vitamin A deficiency is such a serious problem, Golden Rice is frequently
touted as an excellent example of how beneficial GMO technology can be. Several biotechnology companies,
including Monsanto, Syngenta AG and Bayer AG, waived their patent rights during
the development of Golden Rice varieties, perhaps in part because of the public
relations benefits.
In an effort to find fault
with Golden Rice, critics of GMOs point out that an individual would need to
eat a large amount of rice to ingest the US Recommended Daily Allowance of
beta-carotene. They usually fail to
mention that the US RDA is set to help prevent long-term health problems such
as cancer, and that a significantly lower amount can greatly reduce deaths and
blindness due to Vitamin A deficiency. In addition, newer varieties with more
beta-carotene are being developed, and similar approaches are being used to
enhance the beta carotene content of other crops such as mustard. Mustard oil
is commonly used for cooking in India and Asia, where vitamin A deficiency is
common. At this point, Golden Rice is still a few years away from being ready
for large-scale distribution.
Faster-growing
salmon
Another controversial case
is transgenic salmon, several varieties of which have been engineered. One type produces growth hormone all
year round instead of seasonally, so that it reaches full size in half the time
that it takes wild salmon to mature.
This organism does not have a gene from another fish, but it does use a
gene promoter that is
transgenic. The promoter is the
switch that causes the growth hormone gene to be turned on, and the new
promoter results in the gene always being on.
Concerns about these fish
include the possibility that when they escape (which they will, based on the
record of fish farms) they will out-compete native salmon. Many salmon species are already
threatened because of habitat destruction and over-fishing, and might not be
able to survive this additional insult.
There is also the concern that these fish might interbreed with native
varieties, thus changing natural populations with unpredictable ecosystem-level
effects.
Advocates for transgenic
salmon say that only sterile females are produced, which greatly reduces the
chances of problems. They also believe that farmed fish are so poorly fit for
natural habitats (for example, because they are used to eating fish food rather
than obtaining resources from the natural world) that it is unlikely that
escaped fish ever could cause these kinds of problems.
Other GMOs
A variety of other GMOs are
being grown. For example, a
transgenic papaya
that is resistant to the papaya ringspot virus has been grown in Hawaii
since 1998.
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