Tuesday, August 03, 2004


A molecular biologist speaks

Anti-GM activists have claimed that GM transgenes are unstable and will escape and contaminate the environment; that GM causes cancer; and that GM transgenes can enter our cells or our gut bacteria. But there is no evidence that GM transgenes cause cancer, or that they are particularly unstable or liable to escape. All cultivated crops can cross with wild relatives; there is no particular risk with GM crops. GM transgenes are no more likely to enter bacterial cells or human cells than any other DNA we eat in our food - and if they do, they don't tend to survive.

It is also often claimed that only large multinational companies desire GM. But many people in the developing world are trying to develop and take advantage of these technologies. When I published my work on engineering GM plants that resist virus infection, a group of scientists in Pakistan invited me to collaborate with them to solve the problem of a serious endemic viral pathogen that was causing them to suffer 30 per cent yield losses in their cotton crop. Cotton and the associated textile industry bring 60 per cent of foreign exchange earnings to Pakistan, and so this loss to viral pathogens represents an annual loss of about US$500million. Using public sector funding, the scientists have recently demonstrated in field trials that GM cotton is resistant to vial infection.

So where is the evidence that the current generation of GM crops are beneficial for neither people nor planet? Modern agriculture can certainly damage the environment: over the past 50 years, the need to increase food production has resulted in the loss of one-fifth of the world's topsoil, one-fifth of its agricultural land and one-third of its forests. One solution is to develop new technologies to make agriculture more efficient. Greater efficiency means less agricultural land is required, and so more land can be left wild.

Current varieties of GM crops include those that are insect-resistant and those that are herbicide tolerant. Both require lower inputs, such as spraying, and so are particularly suited to small-scale farmers in the developing world.

Modern agriculture involves the use of powerful toxic pesticides - including copper, often used by organic farmers - which enter the groundwater and can damage the environment and human water supply. Spraying pesticides requires expensive equipment and protective clothing, and can also damage the health of farmers who have to spray them. Insect-resistant GM technology here offers a biological solution that organic farmers should embrace: the Bt crop varieties, for example, express a natural insecticide that organic farmers have sprayed on their crops for many decades. Rather than using inefficient spraying, the plant is armed against its specific insect pests - for example, in maize, the corn-borer, which leads to infestation by fungal pathogens that produce mycotoxins.

Meanwhile, GM crops designed for herbicide resistance can be sprayed with a safe biodegradable herbicide. Less spraying is required, again reducing equipment and labour inputs. Another benefit is that agricultural land doesn't require such extensive tilling, which reduces soil erosion and allows more humus to accumulate in the soil.

This is just the beginning. The future holds promise for new GM crop varieties with increased tolerance of drought, heat and cold; with improved disease resistance or nutritional value; or as production systems for pharmaceutical compounds (such as edible vaccines for the developing world) and renewable industrial compounds (such as biodegradable plastics). That's why GM technology is of benefit to both people and the planet.


Many people would like to be kind to others so Leftists exploit that with their nonsense about equality. Most people want a clean, green environment so Greenies exploit that by inventing all sorts of far-fetched threats to the environment. But for both, the real motive is to promote themselves as wiser and better than everyone else, truth regardless.

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