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.
Is gene technology natural?
Will it affect my health?
How will gene technology affect the environment?
Are there markets for GM crops?
Will genetically modified crops help feed the world?
Will GM technology benefit us?
Is gene technology natural?
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?
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?
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?
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.
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.
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.
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?
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?
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.