Genetically modified (GM) crops are varieties that scientists have developed by altering the structure of their genetic material (DNA) to make them exhibit specific new traits.
They were first grown commercially in 1996 and since then their use has grown almost 100-fold. By 2010, they were being grown on nearly 150 million hectares of land in 29 countries.
GM crops include both food and non-food crops (such as cotton). They have proven controversial for a number of reasons, and both public debate and media coverage about them has tended to be highly polarised.
The advantage of genetic modification is that new traits can be introduced into crops far faster and with more precision than by traditional plant breeding techniques.
To achieve this, scientists either remove or deactivate genes from a crop’s existing DNA, or insert new genes into the DNA.
The new genes can come from plants that could normally breed with the modified crop or from a very different species (which can be another plant, a bacterium or even an animal). In this case the GM crop can also be called a ‘transgenic’ crop.
Critics raise concerns about the safety of GM foods, risks to the environment and the fact that GM crops tend to be patented varieties controlled by large multinational corporations (see below).
While some countries have embraced GM crops, most have either rejected GM them outright, imposed a temporary ban, or are waiting to conduct research and develop relevant laws before allowing them.
Scientists are trying to develop GM crops for a number of reasons: to improve crop yields, to boost the nutritional quality of foods, to make crops tolerate drought, among others.
Most GM crops that have been commercialised, however, are of just three species (maize, cotton and soybean) and most exhibit one of two main traits.
Some – such as maize — have been modified to tolerate exposure to herbicides, which means that farmers can spray their fields to kill weeds without harming their crops. Others – such as cotton — have been modified with a bacterial gene that creates a toxin that harms insect pests.
CRITICISMS OF GM CROPS
GM crops have been heavily criticised, especially by nongovernmental organisations, but also by scientists and farmers.
The strongest arguments against GM crops are that they do not boost yields or improve farmers’ incomes to the extent that their proponents claim. Indeed, some GM crops have lower yields than their conventional counterparts.
The International Assessment of Agricultural Knowledge, Science and Technology for Development – a two year effort by hundreds of scientists — concluded that GM food was not a solution to world hunger and that small-scale approaches such as conservation agriculture were the way forward.
The UK government, along with 57 others, approved that report in 2008, but three years later a new study that it commissioned – the Foresight study on Global Food and Farming Futures – stated that GM crops should not be excluded on ethical or moral grounds.
Another major criticism is the introduction of GM crops can make farmers dependent on expensive seeds and other farm inputs made by powerful multinational companies.
When these companies patent the new seeds they develop, they are trying to protect the investments they have made in agricultural research, but many people oppose any form of patenting of life forms.
Patenting also tends to concentrate the ownership of resources and drive up costs, which for poor farmers can be prohibitive. It can undermine traditional practices such as when farmers save seeds from one year to the next, exchange them with other farmers, or use them to breed their own new varieties of crops.
Not all GM crops are developed by privately companies, though, as some publicly funded research centres are also trying to develop GM varieties as global public goods.
Other arguments against GM crops – that they pose a health threat to consumers or a genetic threat to wild species or to non-GM crops – are not well supported by scientific evidence. This does not mean however that no threat exists, but it suggests that GM crops should be monitored and regulated carefully, especially as the process of genetic modification could have unforeseen and unintended consequences.
GM crops usually go through a series of tests before they can be grown commercially. These take place initially in laboratories or ‘biosafety’ greenhouses before the crops can be tested in open fields. For GM foods, it is usual for crops to be tested for safety first on animals and then on human volunteers.
The UN Convention on Biological Diversity’s Cartagena Protocol on Biosafety makes it compulsory for nations to pass biosafety laws before they can grow GM crops commercially. These laws are intended to ensure that countries can ensure that the development and use of GM crops and other organisms do not threaten human health or the environment.
The protocol was created to protect biodiversity from any potential threats that genetically modified organisms might pose. It allows countries that are party to the protocol to ban imports of GM organisms, requires exporters to label any shipments that contain GM products.
Genetically modified crops polarise opinions sharply and journalists should be wary of the claims of both the pro (e.g. biotechnology industry) and anti (e.g. environmental organisations) camps, which both have their own biases.
Indeed, to report effectively on this subject, journalists will need to do more than just present the two opposing extremes of view.
One important thing to remember is that the term “GM crops” covers a huge range of different types of crops that have been modified for many different reasons. So it is often not useful to report on them as a group, or to compare one kind of GM crop with another.
Reporters should also take care when comparing the yield of a GM crop with its non-GM counterpart. This is because the GM crop might not have been modified with the explicit aim of increasing its yield.
When reporting on what farmers think about GM crops it is important to look beyond the simple story of how the crops fares in the field and instead consider the economic and social dimensions of what it means for a farmer to use (or not use) a GM product.
This means looking not only at whether GM crops are safe for consumption and the wider environment but also at how they will be used and who will ultimately benefit from their use (e.g Farmers? Consumers? Multinational corporations?).
Reporters should also note that GM technology is just one of many other types of agricultural biotechnology (such as cloning and tissue culture), but often they are all lumped together and either praised or criticised.
For more discussion of how to report on GM crops, read this article by Curtis Brainard in the Columbia Journalism Review and this SciDev.Net editorial by David Dickson.
CASE STUDY: Golden Rice
More than 100 million people worldwide do not have enough vitamin A. This causes 1-2 million premature deaths and around half a million cases of permanent blindness. One way to overcome this is with dietary supplements — such as pills or injections – but another is to more eat beta-carotene, which our bodies convert into vitamin A.
Beta carotene exists in rice, which is a staple food in many countries where vitamin A deficiency is a health problem, but not in the parts of rice that people eat. In 2000, after 8 years of research, scientists created ‘Golden Rice’ a new GM variety that produces beta-carotene in the parts that people consume.
This GM variety contained two foreign genes — one from the daffodil plant and one from a soil bacterium – that were inserted into the rice DNA in a way that ensure they were only activated in the parts of rice that we eat.
With further research, scientists produced ‘Golden Rice 2’, using a gene from maize to produce 23 times more beta carotene than the original GM variety. Tests with volunteers show that people can absorb the beta-carotene in Golden Rice but so far none is available as food as it has yet to clear the regulatory procedures.
More than 30 companies that hold the intellectual property rights to the processes and products involved in making Golden Rice but they have agreed to grant ‘humanitarian use licences’ to subsistence farmers to enable them to use the rice, and keep and replant the seed.
Opponents of Golden Rice say it would be better to encourage people to eat a more a varied diet containing foods rich in vitamin A such as sweet potato, leafy green vegetables and fruit. Others fear that acceptance of Golden Rice would make it easier for companies to promote other GM crops.
International Assessment of Agricultural Knowledge, Science and Technology for Development
Foresight: Global Food and Farming Futures
Cartagena Protocol on Biosafety
Guardian: The war over GM is back. Is the truth any clearer?
International Service for the Acquisition of Agri-biotech Applications (ISAAA)
SciDev.Net – Agriculture and environment pages
The Golden Rice Project