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Genetic modification: a thorny issue

The ancient Greeks did not have a good grasp of genetics. A giraffe, they thought, was a cross between a camel and a leopard, and an ostrich was the result when a camel mated with a sparrow. A tough task for the bird, one would think. Why did they hold such beliefs? Because in the absence of facts, imagination stepped in. And it still does.

The ancient Greeks did not have a good grasp of genetics.聽A giraffe, they thought, was a cross between a camel and a leopard, and an ostrich was the result when a camel mated with a sparrow.聽A tough task for the bird, one would think.聽Why did they hold such beliefs?聽 Because in the absence of facts, imagination stepped in.聽And it still does.聽A recent survey showed that a third of all Europeans believe that tomatoes only contain genes if they have been genetically engineered.聽Otherwise they are 鈥済ene-free鈥 and one would guess, in their eyes, 鈥渞isk free.鈥

Such surveys are undertaken to gauge public reactions to genetically modified foods, the hottest potato in the area of food safety to come our way probably since the introduction of pasteurization in the early 1900s.聽Activists back then advised people to spurn the new process because it destroyed the nutritional qualities of the milk and even described the horrors that could arise from consuming 鈥渄ead bacteria.鈥澛燭he truth of course was that live bacteria were the ones worth worrying about.聽Of course, there are still holdouts who promote raw milk.聽 They can have it.

Today鈥檚 boogey man is not pasteurization but genetic modification.聽Just about everyone has an opinion on the subject, but much too often this opinion is based on hearsay and emotion rather than on scientific data.聽Consumers speak of 鈥淔rankenfoods鈥 and activists attack and destroy experimental fields planted with modified crops while at the same time they clamor for more research into the effects of such crops.

I am not going to suggest that there aren鈥檛 some contentious issues about genetic modification.聽Of course there are, just like with any new technology. And I鈥檓 certainly not going to say that scientists can absolutely guarantee that genetic modification of foods will have no pitfalls.聽Nobody can make such a guarantee.聽 Indeed, demanding unqualified assurance about the safety of genetically modified foods is just plain naive.聽We don鈥檛 make such demands in other aspects of life.聽 We don鈥檛 say that we will not fly in an airplane unless we are assured that it will not crash because we realize that this would be an absurd request.聽We fly because in our mind we know that the benefits outweigh the risks.聽This is also how we have to look at genetically modified foods.

First of all, let鈥檚 understand that just because something may be good for Monsanto, Novartis, AstraZeneca or any other company involved in biotechnology, it isn鈥檛 necessarily bad for the public.聽But if you listen to some alarmists, you can get the impression that these companies are trying to foist poisons on us purely for the sake of profit. Of course, there is a buck to be made.聽But profits come with the production of good and useful products.聽No company wants to undermine its existence by marketing dangerous substances.聽A great deal of of research has gone into genetic modification and its safety aspects.聽Many of the potential problems that are now being vocalized by opponents were in fact addressed long ago by the industry.聽 The testing for allergens in modified foods has been going on since the inception of the technology.聽 In one case, the addition of a Brazil nut gene to soybeans in order to increase the quality of the protein for improved animal feed resulted in the transfer of an allergen.聽In other words, someone with a Brazil nut allergy could have reacted to eating the genetically modified soybeans.聽But the problem was picked up in routine testing and the soybeans, which had been intended to be used for animal feed only anyway, were never marketed.

We should also note that this presents quite a different scenario from non-genetically modified food.聽 We don鈥檛 ban peanuts, or strawberries or fish because some people have allergies to these foods.聽 And these allergies are far more prevalent than the theoretical allergies to modified foods.聽 Indeed, it may be possible to genetically modify peanuts to eliminate the protein that is responsible for allergies.

Opponents of genetic modification suggest that we should be satisfied with the normal process of cross-breeding plants to produce improved varieties.聽 But where is the guarantee that this procedure doesn鈥檛 introduce undesired chemicals?聽 Appropriate cross-breeding can, for example, yield plants that are more resistant to insects.聽 And why don鈥檛 insects attack them?聽 Because these plants contain more natural toxins than other plants.聽 Nobody knows the human consequences of eating these natural pesticides.聽 Why are the activists not demanding that all hybrid plants, or indeed, that all plant foods be tested for natural toxins?

Let me allow for the possibility that genetically altered foods may present some yet unidentified risk.聽 One can always conjur up some theoretical catastrophe.聽 But let鈥檚, however, compare this to the very real benefits that genetic modification can offer.聽 Combatting malnutrition, for one.聽 When people think of malnutrition, they usually think of starving children.聽 But that is not the only kind of malnutrition out there.聽 In fact the most common kind of malnutrition in the world is iron deficiency.聽 This can cause intellectual impairment, suppressed immunity and complications in pregnancy.聽 There are millions of people in the world who suffer from iron deficiency anemia!聽 Most of them subsist on rice as their dietary staple, a grain that contains very little iron, and the iron it does contain is unabsorbable because of the presence of substances called phytates.聽 These compounds bind iron in the digestive tract and substantially prevent it from being transported across the intestinal wall into the bloodstream.

Genetic modification has resulted in a variety of rice that has more iron.聽This was accomplished by inserting a gene isolated from the French bean into the DNA of the rice.聽This particular gene codes for the synthesis of a protein called ferritin, which is an iron storage protein.聽In other words, the rice now can incorporate more iron from the soil.聽Furthermore, another gene, this time from a fungus, which codes for an enzyme that breaks down phytates was also incorporatedthereby making iron more available.

Populations that subsist on rice also suffer from vitamin A deficiency.聽That鈥檚 because rice is very low in beta-carotene, the body鈥檚 precursor for vitamin A.聽Deficiency of this vitamin is a major cause of blindness in the developing world;聽it is estimated that some 250 million children have vitamin A levels low enough to cause impaired vision.聽Lack of vitamin A also predisposes to various cancers and skin problems.

This problem was addressed by introducing into rice four genes which code for proteins that enhance beta-carotene synthesis, two from daffodils and two from a bacterium.聽The rice is yellow, clearly demonstrating that it is now fortified with beta-carotene.聽Experiments are under way to cross the iron-rich rice with the beta-carotene-rich rice to produce a variety of super rice that can alleviate nutritional problems that affect billions of people!

There are many other fascinating possibilities.聽How about genetically modifying foods to contain higher levels of cancer-fighting compounds such as sulphoraphane found in broccoli?聽 Or fresh fruits and vegetables with improved shelf lives? Edible vaccines?聽Crops that will flourish is salty soil?聽 All realistic possibilities.

But I can hear the critics鈥 minds churning away.聽Why am I not talking about Monarch butterflies being killed by corn that has been engineered to contain a gene from the Bacillus thuringiensis (Bt) bacterium to protect it against the European corn borer?聽 Or the possibility of weeds developing resistance through cross pollination from crops that have been genetically engineered to be herbicide resistant?聽Or a study that claimed rats fed genetically modified potatoes developed gastric problems?聽 Simply because in my judgement, based on the available scientific literature, these concerns have been addressed and either found to be unrealistic or solvable.聽 Surrounding a corn field with a few rows of non-Bt corn, for example, minimizes the Monarch butterfly problem.

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