Sci-fi writers often describe worlds where genetic engineering has gotten
out of hand, and has destroyed some aspect of society. But how
likely is this to really happen?
Misconceptions
Saturday morning cartoons capitalize on the notion that scientists plunge
into the unknown without concern for the consequences. They don't.
A scientist is not, in all probability, going to create a supervirus or a
man-eating plant just to see if he can. Scientists realize the
possible effects of all their research, and stop if there's a possibility
of danger.
Precautions
Experience has shown that when one aspect of nature is changed, there can
be unexpected repercussions in other areas of the ecosystem or in the
economy. Because of this, scientists must be very careful about
making sure that any new organism that they create will not damage the
life that already exists. Let us use the example of genetically
altered fish. After much labor, scientists have succeeded in
creating a fish that grows up to 40% faster than the average fish.
The goal in this research was to make fish for human consumption that grow
faster, and are ready for harvest sooner.
The first step toward assuring that the fish are viable and safe is to put
them in a microcosm, an enclosed, controlled replica of the ecosystem in
which they were designed to live. During this time, the scientists
monitor the fish to see if the implanted gene is working properly.
They are also looking to answer several questions that will determine if
the fish are safe to release into the wild.
- Will the organism survive?
If the fish can't survive in the wild, it goes "back to the
drawing board". Fortunately, this new fish is capable of
living on its own. TEST PASSED.
- Does the organism reproduce,
and if so, how fast? If it multiplies rampantly, it may be a
disastrous addition to the ecosystem, upsetting the delicate balance.
If it does not multiply at all, it still passes this test, but it may
be advantageous to allow the organism to multiply. Scientists
find that the fish is capable of reproduction, and at a normal rate.
TEST PASSED.
- Does the organism have an
advantage over other organisms, and if so, does it compete for the
same resources? Imagine the catastrophe if an organism was
so strong and took so many natural resources out of the environment
that it killed off all its neighbors! Scientists need to find
out if this organism will lead to the extinction of others.
Unfortunately, this fish competes for the same resources as normal
fish, and wins. Because it is growing so rapidly, it needs a lot
of food. It would probably eat the other fish out of a habitat.
This, coupled with its size, could lead to the destruction of the
ecosystem. TEST FAILED.
- Can the gene move to other
species? There is no way to predict what will happen when a
fish with an altered gene is bred with a normal fish. Just in
case the gene would be harmful in other organisms, the scientists need
to make sure that the gene cannot be passed along.
Unfortunately, scientists find that the growth gene in the altered
fish can be passed on to other fish. TEST
FAILED.
- Does the organism
leave the test area? This may sound scary at first, but
basically scientists want to know whether the organism will move
itself to anywhere habitable or whether it will mostly stay where it
is released. In the case of our fish, their ravenous appetite
almost forces them to move on in search of more food. TEST
FAILED.
The genetically altered, fast-growing fish
have failed three tests. The scientists must change the fish so that
they pass all the tests, or they cannot be released. In order to
pass the fourth test (can the gene move across species), a third
chromosome is inserted. This third chromosome keeps the fish from
being able to form gametes with the correct
number of chromosomes. Offspring cannot be conceived, so the fish do
not reproduce at all. No children means no gene passing. In
order to pass the fifth test, the fish are enclosed under three layers of
fencing, one of which is electrified. With the fish placed in this
controlled environment, the third test is automatically passed; there are
no other fish with which to compete.
Ripples
There are other implications from genetic engineering besides danger to
health. For instance, the plant that usually gives us canola oil can
be modified to produce lauric oils, which were once only produceable in
Southeast Asia. While it is cheaper and more efficient to grow the
new plant than to buy the old, American money is not going into Southeast
Asia to buy the oil. The Southeast Asian economy has been effected
by the new plant.
Fruit is being genetically engineered to stay fresh longer. However,
many suspect that this is a counterfeit freshness; the vitamins and
minerals that are the reason to eat fruit at all are gone long before the
fruit begins to go bad. This has made the fruit about as healthy as
a regular, processed food, even though it appears very ripe.
Some farmers use a crop with a built-in insecticide that kills pests.
As always, there are certain bugs that are resistant to the insecticide.
The insecticide gives the mutant bugs a competitive advantage, and there
is a threat that they will multiply rampantly with the farmers providing
their food source. Another insecticide must be used on these bugs,
which is dangerous to helpful insects as well as the crop. Farmers
have had to plant standard crops next to the engineered ones so that the
original bugs are still being provided with food and can multiply, keeping
the resistant strain of insect from having and advantage.
Even though new organisms don't appear to hurt, the lesson is that they
may not help, and may even be causing damage in places that were totally
unpredictable. Great care must be taken when altering the
tried-and-true genetic code that already exists. |