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Arguments for and
against gene technology |
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Gene technology refers to
the direct alteration of the
genetic material of living
things so they may produce
new or modified substances,
or perform new or changed
functions. As with any
technology, gene technology
carries with it risks as
well as benefits. This fact
sheet lists some of the
current questions raised
when considering gene
technology, and summarises
the key arguments for and
against gene technology and
its applications. |
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Is gene technology
natural?
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The argument for
- Gene technology is
another step along the
path of genetic
improvement, which began
with people selectively
breeding plants and
animals for desirable
characteristics thousands
of years ago.
- Many plants and
animals have tens or
hundreds of thousands of
genes. Adding one or a
few new genes using gene
technology is a tiny
change to the overall
genetic makeup of a living
thing. In contrast,
conventional breeding
technology and other
methods of genetic
modification (including
mutagenesis by chemical or
radiation treatment)
involves the change and/or
transfer of many genes.
- Gene technology allows
for the specific
manipulation of one or two
genes. In contrast,
conventional breeding
technology and other
methods of genetic
modification (including
mutagenesis by chemical or
radiation treatment)
involves the change and/or
transfer of many genes in
a less specific way.
The argument against
- Gene technology is
quite different from
historical genetic
modification techniques
that involve breeding
within a species or
between very
closely-related species.
Gene technology enables
the transfer of genes
across species barriers,
and this has virtually
never happened before,
even over evolutionary
timescales.
- Species have evolved
with their genes working
together in complex
systems. We cannot predict
what might happen when an
existing gene is broken up
by the insertion of
foreign genes into an
organism, or what the
effects of a foreign gene
might be on other
apparently unrelated genes
or traits. Also, rapid
alteration of a species by
gene technology could have
unforeseen consequences in
ecosystems that are not
adapted to the new version.
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Will it affect my
health?
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The argument for
- There are strict legal
requirements that control
the development, release
and use of genetically
modified organisms (GMOs)
in Australia.
- The Office of the Gene
Technology Regulator (OGTR)
protects the health and
safety of people and the
environment, by
identifying risks posed by
or as a result of gene
technology, and by
managing those risks
through regulating certain
dealings with GMOs.
- Food Standards
Australia New Zealand (FSANZ)
carries out a thorough
risk assessment of all
food derived from or
containing ingredients
from GMOs before they can
be sold. This includes
examining whether the food
has additional allergens
or toxins as a result of
the GM process.
- While genes that
provide for antibiotic
resistance have been used
as markers in GM plants,
the antibiotics involved
are not usually those used
in medicine. It is
extremely unlikely that
these genes could transfer
from plants to bacteria as
there are a number of
barriers to such
transfer. There are
several common marker
genes that do not confer
antibiotic resistance.
The argument against
- Added genes could make
‘safe’ plants produce
toxins or allergy-causing
substances.
- GM foods are quite
new, and there have been
no studies of the
long-term effects on human
health.
- Antibiotic resistance
marker genes are a type of
marker gene derived from
bacteria. They provide the
bacteria with natural
resistance to particular
antibiotics. They are
sometimes used in GM
plants to find out whether
the added gene has been
taken up by the plant. If
such an antibiotic
resistance gene moved from
a GM plant to a bacterium
that causes human disease,
the antibiotic to which
the marker gene provides
resistance may no longer
be useful for treating the
disease
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How will gene technology
affect the environment?
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The argument for
- GM crops such as
insect-resistant Bt
cotton reduce pesticide
use by farmers and are
therefore less harmful to
the environment, and to
some beneficial insects,
than synthetic chemical
insecticides. Bt
cotton contains a gene
from the bacterium
Bacillus thuringiensis.
This makes the cotton
produce bacterial toxin in
the plants, which acts as
a pesticide designed to
kill only target insect
pests. Herbicide-tolerant
crops allow farmers to
spray less toxic
herbicides than
commonly-used
herbicides.
- Herbicide-tolerant
crops allow farmers more
weed control choices,
including in some cases to
spray less toxic
herbicides and employ
conservation tillage
practices which can
decrease soil erosion and
water loss.
- Transfer of herbicide
tolerance to weeds is a
concern not only with some
GM crops, but also with
conventionally-bred crops.
- Research suggests that
the frequency of transfer
of genes from GM crops to
related crops and weed
species under Australian
conditions is actually
very low. In addition,
precautionary steps, such
as the use of ‘buffer’
zones around GM crops, can
be used to further reduce
the risks of gene
transfer.
- Gene technology can
produce crop plants that
have genes from hardier
plants added to them,
allowing them to tolerate,
for example, salinity,
drought or poor soil.
- Gene technology may
produce plants that are
better at taking up soil
nutrients and so do not
need as much artificial
fertiliser, reducing
run-off to the
environment.
The argument against
- Bt pesticides
may ‘leak’ out of GM plant
roots, harming non-target
insects and soil microbes
in addition to the pests
they are designed to kill.
- Farmers will still be
faced with pests becoming
resistant to pesticides,
even if pesticides are
engineered into crops.
Therefore, GM crops do not
offer much advantage over
existing ways of dealing
with pests.
- Some
herbicide-tolerant plants
may transfer their
tolerance to related
plants, creating
‘superweeds’ that are not
easily controlled by
environmentally friendly
herbicides. This would
increase the use of more
toxic herbicides.
- The use of
herbicide-tolerant crops
encourages farmers to use
more herbicide because the
risk of killing
post-emergent crops is
reduced. This will have a
damaging effect on the
environment. In addition,
the companies that produce
herbicide-tolerant crops
often manufacture the
corresponding herbicide,
which locks farmers into a
single supplier.
- GM plant varieties may
not be ‘stable’ in the
long-term. Their gene
combinations may be more
susceptible to sudden
changes.
- Growing GM crops that
are more tolerant to
drought or poor soils may
encourage farmers to
encroach on lands not
suited to agriculture,
resulting in more
environmental damage than
leaving these lands unused
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Are there markets for GM
crops?
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The argument for
- It appears that yields
from GM crops are
generally higher, so a
farmer may earn more from
the same crop area.
- Research shows that
most export markets for
Australia (such as Japan)
are prepared to buy GM
crops.
- Markets that ban GM
products can be replaced
with those that tolerate
low levels of GM content,
eg. Canada’s GM canola is
now sold to Japan rather
than to the European Union
(EU).
- To date, GM-free crops
have not generally
commanded a higher market
price than GM crops.
The argument against
-
Australia’s ‘clean,
green’ image may be
harmed by the
introduction of GM
crops.
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Many countries, such as
in the EU, do not want
to buy GM products so
farmers may lose markets
if they grow GM crops.
Farmers may also be able
to get a price premium
in some markets if they
can certify that their
crops are GM-free.
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One hundred per cent
segregation of GM and
non-GM products will be
difficult to achieve and
the costs may outstrip
any potential benefits
to farmers from GM
crops.
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The costs of identity
preservation processes
may also deter buyers of
GM products
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Will genetically
modified crops help feed the
world?
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The argument for
- Gene technology has
the potential to develop
plants that are more
nutritious and yield
bigger harvests than
conventional plants and
are at the same time more
resistant to diseases and
to stresses like drought.
One example is ‘golden’
rice, modified to contain
the molecule from which
the body forms vitamin A.
The vitamin, which is
often deficient in people
with poor diets, is
essential for good health
and prevents blindness.
- Gene technology may
help produce animals that
are more productive or
resistant to parasites and
diseases, thus improving
livestock quality in
developing nations.
- GM plants that can
grow in poor soils will
enable countries with poor
lands to be able to grow
more of their own food and
reduce land-clearing.
The argument against
- Feeding the world is
more to do with politics,
economics and population
than hi-tech developments.
Poor countries often
cannot afford to buy from
the food surpluses in rich
countries. Also, poorer
nations are often
encouraged to clear land
and grow cash crops and
animals for export, rather
than subsistence crops to
feed their population. GM
crops will not alleviate
these issues.
- GM crops such as
‘golden’ rice may be
considered an unnecessary
way to achieve the same
result as, for example,
programs to grow pumpkins
in communities, to provide
vitamin A as well as many
other nutrients.
- Poor farmers will not
be able to afford the GM
seeds and related
herbicides they need from
multinational companies,
who are primarily
interested in making a
profit
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Will GM technology
benefit us?
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The argument for
- Farmers may benefit
because of the potential
for increased yields of
crops, healthier animals,
fewer diseases and lower
costs of production.
- There could be some
environmental benefits
because of the reduction
in the use of toxic
chemicals, as well as the
potential to grow more on
less land.
- Humans and animals
will benefit through
better quality, more
specific drugs to treat
diseases and genetic
conditions.
- Multinational
companies have already
freely shared some of
their GM technology with
developing nations.
The argument against
- As with introduced
exotic species, once GM
crops and animals are out
in the environment they
cannot be recalled; they
may cause ecosystem
changes that cannot be
reversed.
- Farmers could be tied
in to multinational
companies selling patented
seed and associated
chemicals at greater cost.
Farmers are already being
sued by multinationals for
allegedly growing GM crops
on their land without a
licence.
- Multinationals will
increasingly own
intellectual property in
agriculture thus
dominating world markets.
- Increased costs for
segregation of crops and
animals will probably lead
to higher prices for
consumers
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