There are few people who do not hold a view on Genetic Modification. Those for tend to argue that GM holds the key to feeding a world with a growing population and a changing climate. Those against tend to focus on corporate greed and the risk to environment and human health. Too often the claims from both sides are extreme and ignore many of the realities and the issues at hand.

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What is Genetic Modification?

Genetic modification is the deliberate alteration of the gene sequence of an organism, either by adding or taking away a gene or by silencing a gene so that it is no longer active. Very often the crops under discussion are the result of inserting a gene extracted from the cell of one organism into the cell of another, for example taking the gene that makes one strain of rice tolerate being deeply submersed in water and inserting it into another strain of rice which will only grow in shallow water.  This is usually done in one of two ways.

 

The mechanical method of inserting the new gene into a cell literally shoots gold or tungsten particles (like miniature bullets), liberally coated with the new genes, into the target cell using a ‘gene gun’. The cells that survive the process will very likely have the new gene embedded in their cytoplasm. This is called biolistics.

 

The biological method employs the natural ability of a particular pathogen (often Agrobacterium tumefasciens, the bacterium that causes crown gall) to insert its genes into the cells of other organisms. The new gene is attached to the bacterium and when the bacterium invades the target cell, it handily takes its gene hitchhiker in with it.

 

However (and predictably) the story doesn’t quite end there. To make the new gene work there must be several other elements attached to it including a marker gene which is antibiotic resistant.  When the Petri dish containing the cells is treated with antibiotics, only those that have been successfully modified will survive. The surviving cells in the dish are then placed in a growing medium and are grown on into new plants. Within the DNA of the new plants will be the new gene that will endow that plant with a new characteristic - a new strain of rice, perhaps, that has the characteristics of the old rice plus the ability to withstand submersion.

 

The first genetically modified plant was produced in 1982.  By 1994 the first commercial GM food, the Flavr Savr tomato,  appeared on supermarket shelves and although it never fulfilled its commercial promise and was removed from sale only three years later, it was soon followed by GM maize, rapeseed, cotton, soybeans, wheat, alfalfa, potatoes, rice, sugar beet and squash, among others. The vast majority of GM seed grown commercially have come about as a result of laboratory research by biochemical giants such as Monsanto, AstraZeneca, Bayer Cropscience, Pioneer DuPont, Syngenta, and Dow Agrosciences, among others.

 

Up to this point there are no GM crops currently being grown commercially in the UK, but there are GM field trials being conducted on wheat, and others are planned for the future.

 

For or Against?

Reasons touted for developing GM crops are many and complex. They include increasing shelf life, improving the nutritional value of plants, breeding herbicide resistant varieties and varieties that can resist disease or insect infestation and breeding plants which can live in extreme conditions, as well as breeding plants specifically to use as biofuels, to produce agents that can be used in pharmaceuticals or as bioplastics, or to render a plant suitable for bioremediation. Specifically the argument for using genetic modification to breed new plants rather than relying on other means is the speed and the relative precision of the procedure.

 

The arguments against GM foods is largely based on distrust in the giant biochemical companies and in their management of this new science,  fears for human health, the health and sustainability of the environment, establishing monocultures and removing genetic diversity.  But probably the largest and most unquantifiable fear is that we are messing with nature by introducing genes into cells which were never meant to be there and we don’t know what the long term consequences of that might be.

 

Some of these gene transfers will undoubtedly have unforeseen consequences. A gene which is introduced into a plant to change the colour of a flower may also produce a protein that triggers allergic reactions in some people, for example. That is because a single gene does not necessarily only determine a single characteristic.

 

Rigorous testing will screen out many potentially dangerous strains, and indeed have done in the past. But it is impossible to foresee all the possible consequences of modifying anything. This is as true in naturally occurring mutations as in mutations that have been engineered in a lab. However until the public are confident in the efficacy and transparency of the agrichemical companies it is unlikely that such fears will go away.

 

GM technology can encourage the indiscriminate use of weedkillers with the development of herbicide resistant crops, like wheat, soya and corn. As these crops are unaffected when sprayed directly with herbicides then it is easy to imagine the less than careful application of herbicides because it is no longer essential to spray carefully.  However some weeds are developing a natural resistance to the herbicide and in some areas farmers are applying larger and larger quantities of chemicals in order to kill increasingly resistant weeds. The biochem company’s answer to this is to develop new strains of crops that are resistant to more than one chemical, to enable the farmer to spray his fields in rotation and so outwit the resistant weeds. The obvious question is how long will it take for the weeds to develop resistance to both chemicals? Clearly there are new breeds of superweeds being bred across millions of hectares of the world, and they are doing it, not with the aid of people in lab coats, but with the tried and tested method of survival of the fittest.

 

The long term effect on human health of pesticide residues, for instance from herbicide resistant crops, has not been addressed. When farmers had to avoid spraying the crop plants with the chemical weedkillers there was a certain assurance that the residues would be below a certain level.  

 

Introducing a gene (often from the bacteria Bacillus thuringiensis, or Bt) in wheat, soya, cotton maize and other crops to imbue insecticidal properties aimed to kill pest insects who fed on the crops before they had a chance to breed thereby controlling the likelihood of the insect population developing resistance to Bt.  However poor weather conditions and late season slow-down cause plants to produce less Bt, which reduces the kill capacity and allows insects to ingest Bt in small amounts. The result is the inevitable development of resistance to first generation Bt.  There are now several strains of Bt crops, and more are being developed.

 

Initially the use of pesticides does, indeed, decrease, but over time and with the development of increased resistance in primary and secondary pests, studies have demonstrated that farmers tend to need to increase spraying regimes, year on year. There remains the fear of poisoning non-target species or beneficial insects and more rigorous trials need to be conducted.

 

What are the biggest problems in the GM controversy?

Undoubtedly the biggest problem is one of trust and transparency.

There is a myth that GM seeds only produce plants with sterile seed, which denies subsistence farmers the chance to save their own seed.  Indeed there was a move early on to develop ‘terminator seed’ that would cause all second generation seeds to be sterile, however it caused such a furore that all companies dropped this technology. But still this myth persists.

 

Giants like Monsanto do however retain rights to the seed they sell to farmers; the sale is subject to a Monsanto Technology/Stewardship Agreement which decrees that no seed can be saved to grow on into next year’s crop. To counter this there is the very valid argument that farmers can choose to buy seed that is not produced by one of these companies and has no restrictive clauses attached. 

 

The restrictions over what can be done with seed are waived in some instances, as in the case of Golden Rice. The golden colour, a result of genes borrowed from daffodils and bacteria, endows this rice with increased levels of beta-carotene, a building block of vitamin A. The strain of rice was developed by scientists in Switzerland and Germany to combat lethal vitamin A deficiency in developing countries. When it is rolled out it will be offered to small farmers free of any restrictive clauses, provided the grower has an income below a certain amount. That means that some farmers will be able to grow this strain of GM rice without any restrictions, and so can be feed their family and local community with a foodstuff that will eradicate the many effects of Vitamin A deficiency, including rickets, scurvy and blindness.

 

The same restrictions that control what the farmer does with his seed, restricts independent researchers from conducting field trials and laboratory experiments unless they have the specific permission of the controlling corporation. This ownership of the seed and the progeny of the seed ad infinitum is a point of enormous controversy. Monsanto has granted unrestricted research rights to about 100 universities across America. Other crop biochem companies negotiate rights on a case by case basis, but most of these seed giants retain the right to terminate the agreement if they disagree with the methodology or findings of the tests, and they may then withdraw permission for the publication of the results. Although that is understandable as a marketing strategy, as far as the advancement of science, gaining the trust of the public and ensuring ethical behaviour it is a pretty poor choice.

 

However, given the vociferous lobby against GMOs it is understandable that the crop biotech companies need to protect their investment against poorly organised or implemented studies and trials that are out of their control. Any study that came up with a damaging report (even if the science behind that report was flawed) would have a massive detrimental effect on the reputation of GM crops as a whole, and on the crop under investigation in particular.

 

The same accusations of weak or shoddy studies are being thrown at the crop biotech companies themselves. Tests on food plants are not as rigorous or as transparent as tests, for instance, on pharmaceutical products, and the lack of transparency and the apparent locked doors to health and environmental safety data, as well as scepticism about the impartiality of the conclusions means that even if the tests are rigorous, the way the information is disseminated lays the science open to cynicism and disbelief.

 

At this point it is pertinent to note that Mutation Breeding (bombarding plant cells with radiation or chemicals to effect a gene mutation) has been around for many, many years and has produced hundreds of plants that are in use today, but all of these plants were randomly mutated, grown on in a Petri dish and then selected if the new traits were desirable. These plants don’t need to be labelled and are permitted for use in organic systems. So what is the difference between these genetically altered plants and those that are developed using biolistics or biological methods? Perhaps it’s simply the sheer scale and impenetrability of the biochem giants that is the real problem.

 

Public and private institutions need the freedom to test these GMOs before they are licensed for commercial use and the biochem companies need to know that the testing will be fair and will continue to protect their intellectual property rights. Agricultural research stations and universities across the world have always conducted tests and field trials on new plants to investigate their suitability for local conditions and to conduct independent trials on their various qualities. Only with GM crops is this testing restricted.

 

And of course it has to be remembered that not all GM crops are developed and distributed by giant biochem companies. The papaya industry in Hawaii was brought back from the brink with the introduction of a virus resistant variety introduced, not by a corporate giant, but by a university research scientist. 

 

The UK based John Innes Foundation is conducting research into developing a strain of maize that will fix nitrogen in the soil in the same way as peas and beans do. If successful, this new crop could be grown by poor farmers in developing nations who can’t afford the nitrogen fertilizers necessary to grow a successful crop. This same technology could lead to a reduced need for high nitrogen fertilizers which are massive pollutants in both the developed and developing world. Is this, then, a dangerous or a beneficial project?

 

It is clear that GM technology will not disappear. Rigorous, transparent and impartial testing both in the lab and in extensive, long term independent field trials will go a long way to allowing lobbyists on both sides to base their arguments on good, sound science.  The future of GMOs must be decided on a crop by crop basis with equal weight being given to the value of the crop, the health of the environment and the sustainability of communities around the world.