GM – Friend or Foe?

Dr Martin Brookes

May 2004

Time was when life was simple. When sheep were sheep, when corn was corn, and when a mouse had four legs and a tail. But now the boundaries have become blurred. There's no longer any guarantee that what you see is what you get. There's a bacterium, for instance, that makes human insulin, a grass that snuffs out hay fever, a mouse that's become a farm for fish oils, and a fish that glows red in polluted water. And don't even mention the food. Old diets are going stale as an alternative type of menu emerges. Forget about the traditional meat and two veg. Now it's all suicidal potatoes and fart-free beans. Welcome to the world of genetically modified organisms, or GMOs; welcome to that surreal and scrambled place where anything seems possible. Where characteristics of organisms can be combined in a new kind of cookery to produce completely novel forms of life.

Genetic engineering is a complex technology with a very simple goal. Its aim is to tailor organisms to meet our own specific human needs. To take a gene that produces an interesting characteristic in one organism and put it in another organism that lacks the gene, but has other characteristics which we like. It's a kind of genetic mix 'n' match; a way of getting the best of both worlds in a single living thing. And like it or not, it looks like it's here to stay.

Bacterial sex

The story began in the 1960s, in the era of free love, when bacteria were tempting young biologists to turn on, tune in and pull on a lab coat. For geneticists, bacteria had been the organism of choice since the Second World War. Their single-celled simplicity and remarkable rates of reproduction made them ideal models for manipulation. By the 1960s it was their sex life that was arousing the most interest, as biologists began to discover the diverse and eccentric ways in which bacteria naturally exchange bits of DNA with one another. Though interesting in themselves, these discoveries suggested revolutionary applications. They hinted at ways of artificially manipulating genes, of shunting them around from one organism to another. In short, revelations about bacterial sex laid the entire foundation of genetic engineering.

Helping diabetics

One of the first commercial uses of genetic engineering was in the production of human insulin for people suffering from diabetes. Insulin is a hormone produced naturally by the body to control the level of sugar in the blood. Diabetics are unable to produce sufficient quantities of insulin themselves. Without self-administered injections of additional insulin, their blood sugar levels can vacillate erratically, often with dangerous consequences. In the era before GMOs, this insulin would come from cows. The problem was, some diabetics were allergic to the cow insulin. Genetic engineering, however, offered a cunning solution. Scientists identified the gene for human insulin, isolated it, and then injected it into bacteria. In effect, the human gene was incorporated into the bacteria's own DNA. Then, as the bacteria grew, they produced human insulin that was quick and simple to harvest.

Genetically engineered insulin set the pattern for the future, and today a whole range of human proteins and hormones are manufactured along similar lines. As traditional industries have declined, bacteria have materialised as the workers in a new kind of factory, where the capacity for production seems almost limitless.

AIDS hope

Bacteria can be put to use in other ways too. In the United States, ongoing research is looking into the possibility of using genetically modified vaginal bacteria as a natural antidote to HIV and AIDS. Researchers at Stanford University in California took the naturally occurring vaginal bacterium Lactobacillus jensenii and engineered it to produce a protein that is known to block HIV infection. In test tube trials, the genetically modified bacterium prevented the HIV virus from infecting human cells. Should the bacterium one day get the go-ahead, it is hoped that it could work wonders in countries where social customs make condoms an unpopular and ineffective deterrent against the disease.

Tough crops

Few people complain about genetic engineering when it is applied to medicine and contained within the relatively secure surroundings of the laboratory. But with its growing success, the technology has moved outdoors, and into far more controversial realms. In the United States, genetic engineering has found a home in the commercially lucrative field of agriculture. Weeds, pests and disease represent some of the biggest problems confronting modern farmers. Weeds alone are thought to account for the loss of 10% of all crops annually.

Farmers can use weedkillers to control their weeds for part of the year, but once the crop is sown and growing, chemicals can kill not only the weeds but the crop as well. So when scientists discovered a strain of bacteria that was resistant to weedkiller, genetic engineering once again offered a solution to the problem. The gene that conferred resistance was identified and isolated from the bacterium and then introduced into soya to produce herbicide-resistant plants. Using this new variety of soya, farmers can now use herbicide and control their weeds much more effectively.

High yields

GM soya is just one among a string of new products that biotechnology companies are promising will revolutionise the global agriculture industry. GM cotton is already being grown in India and sub-Saharan Africa, apparently with great results. The modified cotton plant contains a gene for a bacterial toxin that kills bollworms, a serious pest of cotton in the developing world. In the KwaZulu-Natal province of South Africa, the engineered plants gave over 50% more cotton than the conventional crop during their first year of cultivation. Together with the increased yield, came a reduction in pesticide use. This was not only good for the environment, it was also good for the farmers themselves, who often fall victim to pesticide poisoning.

Suspicious minds

This kind of success story, however, does little to appease the doubters, and the world remains divided on the cultivation and use of GM food. US farmers seem to have wholeheartedly embraced the new technology. Travel to the vast plains of the American Midwest and you will find millions of acres of genetically modified soya and maize. But across the Atlantic, it's an entirely different story. Many Europeans are still concerned about whether GM food is safe for the environment, and safe to eat. It's a fear shared not only by countries in the West, but also in less developed parts of the world, where the spectre of famine is a real concern. Several African countries, including Zambia, remain suspicious about the merits of GM food.

Environmental worries

Environmental concerns centre around the idea that genetically modified plants will disrupt or damage native wildlife. Plants do hybridise readily with one another, and there is always the possibility that genes from a modified crop will end up in all the wrong places. In the most apocalyptic scenario, a gene for herbicide resistance, for instance, would escape from a GM crop, via pollen or seed, into a wild relative. This could lead to the creation of a so-called 'superweed', that is resistant to herbicides. The weed would then rampage through the countryside, outcompeting other native plants and destroying biodiversity.

GM for the UK?

The UK government must consider this scenario unlikely, as it has just given the tentative go-ahead for the first commercial cultivation of a GM crop. From next year, UK farmers will be able to plant and harvest GM maize. The question then, is who will want to eat it? In fact you can already find GM food on your supermarket shelves. GM soya and maize is now frequently used in some brands of bread, cake, margarine and other processed foods. The Americans have been eating it for years, apparently without any ill effects. But for opponents, issues remain over the allergenic properties of GM foods, and the remote possibility of genes jumping from the food that we eat into our own DNA.

While these may represent legitimate concerns, blanket opposition to GM food seems unreasonable. Genetic engineering is a diverse technology. Each new instance of genetic modification creates an organism with characteristics and peculiarities unique to itself. Surely, therefore, the safety and suitability of each new product needs to be considered on a case by case basis.

Age-old tradition

Pervading the whole debate on GMOs seems to be the vague and sometimes crude notion that the technology is wrong because it is unnatural. But human beings moved away from the natural an awfully long time ago. Agriculture grew from the idea that you could take wild varieties of plants and animals and improve them through selective breeding. Just about everything we eat today – from beef to Brussels sprouts – would not exist without the long history of human interference in nature. In one sense, genetic engineering is simply a continuation of this age-old tradition. After all, both genetic engineering and selective breeding have identical aims – to produce organisms that are adapted to the needs of humans rather than nature.

Find out more

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Websites

GM Watch
www.gmwatch.org
Organisation that reports on the growing concerns over genetic engineering and the rapid release of genetically modified foods and crops.

New Scientist
www.newscientist.com
Website of the popular magazine with many reports on GMOs.

Insulin Dependent Diabetes Trust International
www.iddtinternational.org/iddt.html
A charity based in the UK listening to people with diabetes and their carers and supporting their needs, including those experiencing difficulties with genetically engineered insulin.

Food Standards Agency
www.foodstandards.gov.uk/multimedia/
pdfs/gmnewcastlereport.PDF
Technical report on the FSA project 'Evaluating the risks associated with using GMOs in human foods'.

The Genetics Society
www.genetics.org.uk
A 'learned society' whose membership consists of most of the UK's active professional geneticists, including teachers, researchers and students. The society promotes the advancement of genetics for the benefit of the public.

The case against GM crops
www.sgr.org.uk/GenEng/
CaseAgainstGMcrops.html
Article from Scientists for Global Responsibility, a society that promotes ethical science and technology, based on the principles of openness, accountability, peace, social justice and environmental sustainability.

Friends of the Earth
www.foe.co.uk
The website includes a 'Zero tolerance on GM food' section.

Institute of Science in Society
www.i-sis.org.uk
A wealth of information on GMOs, including an article on 'glofish', the genetically modified fish designed to glow in polluted water.

The end for GM crops in Britain?
Article from Channel 4 News website.

Designer baby born
Report on Britain's first designer baby from Channel 4 News.

Books

	Don't Worry (It's Safe to Eat): The true story of GM food, BSE and foot and mouth by Andrew Rowell (Earthscan, 2003) The author tells the story of BSE and exposes how trade and macro-economic policies overruled good science in the foot and mouth catastrophe. He also opens the black box of the so-called GM revolution to expose the myth behind the marketing and tells the true story of the Pusztai GM potato scandal of the late 1990s and the ongoing Mexican maize GM contamination affair. Get this book
	The Genetic Revolution by Dr Patrick Dixon (Kingsway Communications, 1997) Looks at genetic engineering in our food and the risks of future disasters through chemical warfare as well as the feasibility of human cloning and the legal and ethical questions raised. Get this book
	Invisible Frontiers: The race to synthesize a human gene by Stephen Hall (Oxford University Press, 2002) This volume records the race run from the spring of 1976 to the autumn of 1978 to clone a human gene in order to engineer the mass production of the first genetically engineered drug: the life-sustaining hormone insulin. Get this book
	Eat Your Genes: How genetically modified food is entering our diet by Stephen Nottingham (Zed Books, 2003) This book details what these new foods are, how they are produced, why they remain unlabelled and how they are arriving on our plates unannounced, as well as revealing those responsible for driving genetically modified foods so rapidly on to the market. Get this book
	The Ethics of Food: A reader for the 21st Century edited by Gregory E Pence (Rowman & Littlefield Publishers, 2002) Will genetically modified food feed the poor or destroy the environment? Is it a threat to our health? Is the assumed healthiness of organic food a myth or a reality? The answers to these and other questions are pursued. Get this book
	Food, Inc.: Mendel to Monsanto – The promises and perils of the biotech harvest by Peter Pringle (Simon & Schuster Intl, 2003) A balanced and well researched account of the dispute over genetically modified foods. The author exposes the propaganda science and fear-mongering so prevalent in this issue. Get this book
	Clones, Genes and Immortality: Ethics and genetics by John Harris (Oxford Paperbacks, 1998) Looks at the ethical issues surrounding the revolution in biology, which has provided scientists with an unprecedented ability to control human evolution. From designer babies to genetic screening by employers, his book provides a stimulating introduction to the present concerns about the rapid pace of developments in human biotechnology. Get this book
	Seeds of Contention: World hunger and the global controversy over GM crops by Per Pinstrup-Andersen and Ebbe Schioler (The Johns Hopkins University Press, 2001) The authors, both development specialists, focus attention on the less discussed issues of the potential benefits and costs of genetically modified crops for developing countries. They review the basic issues and discuss the potential that such crops have for addressing the great needs of poor and undernourished peoples throughout the world. Get this book
	Genetic Maps and Human Imaginations: The limits of science in understanding who we are by Barbara Katz Rothman (WW Norton & Co Ltd, 1999) Examines the current trends and applications of genetics research on race, illness and procreation and aims to help us think about the place of genetic science in our own lives, its role in our social world and how we choose to think about human life itself. Get this book
	Genes and DNA: A beginner's guide to genetics and its applications by Charlotte K Omoto and Paul F Lurquin Omoto (University Presses of California, 2004) A well rounded introduction to the fundamental theories and practical applications of genetics, written specifically for non-biologists. It covers all the basic concepts from classical and molecular genetics to quantitative and population genetics, including cloning and genetic diseases, and discusses the many applications of genetics to the world around us. Get this book

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