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Is GM safe?
BBC2 9:30pm Thursday 9th March 2000

Genetically modified soya SCIENTIST: We are already probably on the path of no return.

SCIENTIST: A new technique of molecular biology appears to have allowed us to outdo the standard events of evolution.

NARRATOR (ADEN GILLETT): These voices were recorded 25 years ago at a conference of the pioneering scientists of genetic engineering. They had come together to discuss their fears of this new science.

SCIENTIST: There may still be sound reasons why the Pandora's Box should not be opened.

NARRATOR: These scientists worried that some of the new life forms they were creating, organisms never seen in nature, could escape from the laboratory. For fear of alarming the public, they ordered the audiotapes of the conference to be locked away until the year 2000. This is the first time they have been heard.

SCIENTIST: It is not known what sort of risk this is going to create because we have no tests.

SCIENTIST: Such experiments must at a minimum be postponed for an indeterminate period of time.

NARRATOR: But since this conference, many scientists have become convinced that genetic engineering and the genetic modification of food is safe. What has happened in the last 25 years to change their minds? There is a worldwide movement spreading out from Europe to get rid of genetically modified crops, a movement based on the fear of two key things: that GM food is dangerous to eat and that GM crops will damage the environment.

(ACTUALITY PROTEST CHAT)

It is a protest movement that is gathering pace and it has brought the biotechnology industry to its knees. Even the GM giant Monsanto has had to bow to public pressure.

ROBERT SHAPIRO (Monsanto): Our confidence in this technology and our enthusiasm for it has, I think, widely been seen and understandably so, as condescension or indeed arrogance.

NARRATOR: After years of pointing out the dangers of genetic modification, the protesters finally have the scent of victory.

JEREMY RIFKIN (Environmental Campaigner): Genetically engineered foods will be one of the great disasters in the history of introducing a new technology into the market-place. It may be looked back on as a case study of a technology that had no purpose, no market and no reason for being. It probably will fail.

NARRATOR: Are the sceptics right? Are these foods potentially dangerous or will they feed the world in the 21st-century?

(ACTUALITY PROTEST CHAT)

In Monsanto's research centre there are 1500 PhDs, one of the biggest concentrations of scientific brain power in the commercial world. It was here 20 years ago that they did some of the first experiments to genetically modify plants. This is what it's all about - genes, DNA, the blueprint of life. Inside every cell of every living thing there is DNA which is made up of thousands of genes.

Genes produce proteins that have specific functions and it's these proteins that give every plant and animal its unique characteristics. Scientists can manipulate the genetic code of life to produce plants with new characteristics never seen in nature. They can isolate any one gene from any organism like an animal or bacterium and insert it into a completely unrelated species like a plant.

That gene then becomes part of the genetic instructions that make these tiny plants grow. It will give them the same unique characteristic as the original species. The possibilities are almost endless. Scientists can insert a gene from a bacterium into a grape to make it resistant to viruses, or they can engineer maize that resists drought, or potatoes that resist pests, so farmers can use less pesticides on their crops. But these are all plants unknown in nature. They have a foreign gene inside them. People are sharply divided on whether this can be safe.

SIR ROBERT MAY (Chief Scientific Advisor to UK Government): There isn't anything significant to worry about because after all an area twice the size of Great Britain is, and much of it has been for some years, under cultivation with GM foods that have found their way into the food chain elsewhere in the world when there hasn't been a single incident demonstrating anything to worry about.

JEREMY RIFKIN: It's a radically different approach to breeding. Some of it's going to be safe, I have no doubt, but there is not a scientist doing this work that can tell us that all of it will be safe.

DR. ROBB FRALEY (Monsanto): Our knowledge and the precision at which we can work with biotech is actually far greater than what we've experienced traditionally in the thousands of years we've been breeding plants.

NARRATOR: For thousands of years we've been tampering with the genes of plants by traditional breeding. Traditional plant breeders use cross-pollination to introduce new characteristics from one plant to another giving them the genes to grow bigger or taste better than nature intended. Even common plants like the tomato, which for hundreds of years was considered inedible, has been bred to make it palatable, but there's a key difference here. With traditional plant breeding genes cross within the same species, but GM allows plant breeders to break the species barrier and for critics this is fundamentally unnatural.

JEREMY RIFKIN: For 10,000 years since the advent of the Neolithic revolution in agriculture we have been breeding within families, but not beyond families. Here we have powerful tools, especially recombinant DNA, that allows scientists to move from the species and organism level to the genetic code level and treat the genes as independent pieces of information that can be stripped out of any organism in the world and inserted into the code of any other. Example, the gene that emits light in a firefly. Scientists take that gene, they strip it out of the genetic code of the firefly, they insert it into the genetic code of a tobacco seed. The mature tobacco plant lights up 24 hours a day.

NARRATOR: Tobacco can be engineered to glow when it needs watering. By inserting a gene from a foreign species GM is able to add to crops qualities that no amount of traditional breeding ever could. For instance, scientists could isolate the gene that prevents a flounder from freezing in Arctic waters and engineer it into a strawberry so that the strawberry is not destroyed in heavy frost.

(ACTUALITY PROTEST CHAT)

It is precisely because these genes cross the species barrier that protestors believe they could be dangerous.

(ACTUALITY PROTEST CHAT)

They believe it is impossible to know once we have tampered with nature what will happen.

PROTESTOR: When we change the fundamental recipe for life on this planet we have no idea what's going to happen and what we do is permanent and it's forever and we can't ever reverse that.

NARRATOR: The fear is that the proteins produced by these foreign genes might be dangerous, either because the protein itself is poisonous or because it might alter the chemistry at the plant so that the plant becomes toxic.

JEREMY RIFKIN: When we introduce genes into these food crops from unrelated species these are genes that code for proteins many of which we have never put in to our bodies. We don't know what the reaction will be.

ROBB FRALEY: The point is these products are the most thoroughly studied, most thoroughly reviewed agricultural products ever developed by man and I believe that that, in addition to the inherent safety record and the thorough review, is what establishes their safety in the marketplace.

NARRATOR: So who is right? The biotech industry believes that checks are in place to vet their GM food for any health hazards, but the critics say that science cannot predict the unknown. There are a series of specific tests now being used to help government regulators decide whether GM food is any more hazardous to eat than unmodified food.

PROF. TOM SANDERS (UK Committee on Novel Foods (ACNEP): In the case of genetically modified food we want to know exactly what the nature is of the genetic modification, how precise it, the genetic modification that's been and whether there are any unintentional changes that occurred in the food.

NARRATOR: For example, GM soya. We have been eating this ground up ready GM soya in processed food for 3 years, but it contains a gene from a foreign species, a bacterium that lives in soil. Scientists have identified the gene that makes this bacterium able to survive being sprayed by weedkiller. They have extracted this gene and inserted it into the cell of a soya plant and developed this into a crop. In the plant's cell the gene inserts itself into the DNA where it produces a protein that give the soya the same resistance to weedkiller as the bacterium.

Now a farmer can spray his field and kill the weeds but leave his soya crop undamaged. Whether we have eaten this gene before or not its protein has to be tested before it is put into the plant to ensure it is not toxic or allergenic. First, is the new protein toxic?

TOM SANDERS: This was looked at quite carefully by the committee. It took the protein and asked for toxicology test to be done on a protein to see whether the protein itself was toxic.

NARRATOR: The protein has to go through years of testing. For instance, to analyse its chemical properties and heat stability. To test the new protein for toxicity they mass-produce it and feed it to mice. The mice are fed the protein in doses 1,000 times greater than a human would consume by eating GM soya. In these tests no ill effects on the mice were observed from the GM soya protein. Many tests like these have convinced regulators that the protein produced by the bacterial gene is not itself toxic, but there are still many others things to test for.

Everything we eat contains proteins. Even if a food is not actually toxic it could still be dangerous because it might cause an allergic reaction, so the GM protein also has to be tested for allergenicity. Proteins are made up of amino acids. Certain combinations of these amino acids can cause an allergic reaction in humans that can even lead to death, for instance peanut allergy.

TOM SANDERS: We know that most of the allergens have certain amino acid sequences and we can look at the proteins that are introduced in a crop and ask the question: are any of these sequences present in the novel protein and if they're not present in novel protein and we feel more confident that we haven't got a new allergen so it is a safety procedure.

NARRATOR: Scientists have compiled a list of more than 500 combinations of amino acids in proteins that are known to cause an allergic reaction. Every newly introduced GM protein has to be tested against this list.

DR. ROY FUCHS (Monsanto): We have a number of analytical methods that compares the properties of our protein compared to the properties of allergens. That's very important in a predictive mode and those procedures allow us to predict the safety from an allergenic perspective for the proteins we introduce into a plant.

NARRATOR: A key characteristic of these known allergens is that they resist digestion in the human gut. That is one of the reasons they can be dangerous. So among other tests scientists must check that the new protein is easily digested. To do this they recreate the chemical conditions of the human gut, the enzymes and acids, in the test-tube.

ROY FUCHS: We subject any protein that we've introduced in a biotech product to the process we call protein digestion to evaluate whether the protein would be digested when consumed by humans comparable to proteins that are currently in our food supply that are deemed to be safe, so we expose our protein to a solution that mimics mammalian digestion of proteins and ask the question of how quickly that protein degrades.

NARRATOR: The protein to be tested is added to the acidic mixture mimicking the gut in the test-tube. Fast is better. The longer the protein takes to degrade the more concerned regulators will be. If the protein degrades in less than a minute the chances are it will not be allergenic. Then they stop the digestion process by neutralising the acidic solution with alkali. They test to see if the new protein has disappeared broken down by the acidic mixture. The results for GM soya were clear.

ROY FUCHS: In this particular experiment this represents the protein at time zero. Within 15 seconds the protein is completely degraded. Because of its rapid degradation, we can predict that this protein and any other protein that rapidly degrades, will not be an allergen.

NARRATOR: There are a number of other tests to check if the protein itself is an allergen, including a detailed analysis of its precise molecular structure. If a new protein fails these tests it is thrown out. The bacterial protein in the GM soya has passed all these tests. So has every other GM food on the market.

There's yet another stage of testing. Biotech companies now have a range of prototype GM vegetables - tomatoes modified to taste sweeter and lettuce that stays fresh longer - but they have to convince regulators that after the foreign gene is engineered info the plant it won't alter the plant's own chemistry and make it dangerous to eat. This is the concern of critics. When the gene enters the plant's cell it inserts into the DNA of the plant and starts to produce a new protein.

The fear is that this protein could interact with the plant's own proteins and alter the chemistry of the plant itself and the way it functions. So that's why the modified plant now has to be tested on a molecular level to see if there's been any change in its chemistry.

TOM SANDERS: If the metabolism of a crop is deranged you will start seeing changes in the composition of the food. It'll either produce more toxins, less toxins, it will start changing its nutritional composition of the crop.

ROY FUCHS: 80% of all the testing we do for our biotech products addresses that specific question: Have we in any way changed the composition, the presence of important nutrients, are the presence of factors may not be safe for human consumption?

NARRATOR: To test that the edible parts of the GM plant are substantially equivalent to the non-GM version they grind up both and compare their chemistry in minute detail.

TOM SANDERS: We would want to be looking at it for protein composition, fats, carbohydrates, minerals, all the naturally occurring toxicants in there and we have to make a comparison of a food with something, a base and what we would normally take would be the ungenetically modified food.

NARRATOR: Piece by piece they compile the chemical blueprint of the GM plant and compare it with the original unmodified plant. They must prove to the regulators that despite the one gene change overall there will be no difference and if there is no difference they conclude that the GM food is safe to eat.

ROY FUCHS: We've done over 1800 different analyses on 400 different components to show that Round-up Ready soya beans are the same as other soya beans that we consume every day except for the one introduced gene and the protein that gene produces in the plant.

NARRATOR: The system has already caused one problem. A gene from a Brazil nut was engineered into soya to make it more nutritious. During testing, scientists discovered that the protein produced by the gene was allergenic and that the modified soya plant had also inherited the nut allergy and so it was abandoned. Examples like this convince regulators that the testing system works.

TOM SANDERS: What we have to do is look at each GM food on a case-by-case basis. We cannot generalise and say all GM food is going to be safe. It will depend on the nature of the modification, how precisely it's done, whether there are any unintentional effects and whether the food itself when it's processed undergoes under further changes that may lead to, you know, unwanted changes.

NARRATOR: But critics believe that no amount of testing can insure that GM crops are completely safe. They believe that there is too much we don't understand about the complex genetic make-up of living organisms and that even though there is little evidence so far, there may be a risk that genetic modification could cause effects so unexpected that they will be missed by all the tests biotech scientists carry out.

DR DOUG PARR (Chief Scientist, Greenpeace): What can happen as a result of these insertions is that you can in food domain, for example, one can find new allergens, new toxins appearing that weren't expected and because of the complexity of the living organisms these are extremely hard to predict effects.

NARRATOR: Genetic engineers feel the risk of unknowns is extremely small and they argue that as far as safety goes it is unreasonable to demand zero risk for GM crops because that isn't what is expected from traditional methods of plant breeding. For thousands of years traditional plant breeders have improved crops by taking pollen containing all of one plant's genes and cross-pollinating it with all the genes of another. Tens of thousands of genes cross over at random. This system does not require rigorous testing and yet things can go wrong.

In the 70s traditional breeders crossbred two types of potato to transfer the genes for insect resistance. Unwittingly amongst the thousands of genes crossed they also transferred a gene for a toxin that made people ill. In contrast genetic engineers claim their work is safer and more predictable because they are moving just one or two specific genes and they can more easily test the effects.

ROBB FRALEY: A plant breeder crosses two plants and in doing so creates a completely random recombination of 20, 30 or 40,000 genes. Every time you make a cross that, that's what's going on in nature. With biotech what we have is a very precise knowledge for understanding where did the gene become inserted and how is it being transmitted like all the other genes when people make a cross?

NARRATOR: But critics keep returning to the crucial difference that genetic engineering moves genes across the species barrier. This they say makes it inherently more unpredictable and risky than traditional breeding.

DOUG PARR: I don't think anybody can say that traditional breeding is risk free because it clearly isn't, but in genetic engineering when we're using new techniques and inserting genes in a different way then the risks are qualitatively different. They are not the same kind of risks as you get from traditional breeding and where there are examples of foods becoming toxic because of traditional breeding methods, but because they're qualitatively different we are actually quite ignorant about the sort of effects that can arise as a consequence.

SIR ROBERT MAY: On the one hand so-called GM techniques which in the precise and targeted way bring in a couple of genes that you know what they do and you know where they are is vastly safer, vast, vastly more controlled than this so-called conventional breeding that reshuffles about a tenth of the genome. On the other hand, it is true, you can bring in genes from further away, but insofar as I worry about unintended consequences, I worry much more about what we did in the past when we in an unintended way were doing all sorts of things we didn't even know what we did.

NARRATOR: Ultimately, for the protestors, questions about safety and testing of GM food miss the point.

DOUG PARR: Rather simpler to cut through all that and say well why are we needing these things in the first place, what's the point, is there anything particularly wrong with the food we're got at the moment? Well quite clearly for many of the consumers in the UK and Europe the answer's no.

NARRATOR: A year ago there were more than 2,000 processed foods on sale in this British supermarket with GM ingredients. Now there are less than 100. They have been rejected by the British public who see GM benefiting farmers and biotech companies, but not themselves, but there are different concerns for people in the rest of the world. Mexico, like many sub-tropical countries, has poor acid soils and that means that the crops don't grow well. A Mexican peasant farmer has, on average, 5 acres of land to grow the staple crop of maize and unless it is a good year it is hard for him to feed his family. Luis Herrera, a pioneer of genetic engineering, has been studying the stunted growth of Mexican maize for years.

DR LUIS HERRERA-ESTRELLA (National Polytechnic Institute): This maize is not growing very well because the soil is not very fertile. It has problems of soil acidity which lead to aluminium toxicity and low nutrient availability, so what happens is that the root system of the plant doesn't grow and it cannot make, it cannot supply the plant with enough nutrients to grow and what the farmers find is that the productivity of the plant is, is not good. Usually you should have this big and you have very little production.

NARRATOR: Increasing the yield of this maize in the low quality acid soil has become Herrera's lifetime work.

LUIS HERRERA-ESTRELLA: In this acid soil there are two major problems. One is that in these soils aluminium becomes soluble and it's a very toxic compound so in, it reduces root growth and in that way it reduces plant yield. The second problem is that very important nutrients such as phosphate become insoluble and plants cannot use these nutrients.

NARRATOR: Herrera has managed to engineer a gene into the maize that makes it release a natural chemical called citrate which latches on to the aluminium toxin trapping it into the soil away from the plant.

LUIS HERRERA-ESTRELLA: They bind together very tightly and when they are bound this complex of citrate and aluminium is not toxic anymore.

NARRATOR: But the added beauty of this system is that at the same time the citrate releases phosphate from the soil which helps the plant to grow.

LUIS HERRERA-ESTRELLA: So you can see here that the root formation of a normal plant in an acidic soil is not very good and in plants that we produce citrate the root growth is much better and this is a way we have to demonstrate that the system is working.

NARRATOR: Herrera says that if his GM maize was planted in Mexico it could double the yield of farmers' crops, but the Mexican government has stopped Herrera from testing his GM maize in field trials because groups like Greenpeace have been lobbying to halt what they see as a dangerous and unsustainable technology.

LUIS HERRERA-ERSTRELLA: This environmentalist groups have come to Mexico and transferred their emotional interpretation of the technology. They have been putting some pressure into the Mexican government, they want to stop GM plants being grown in Mexico. People speak selectively, only the negative thing and they totally ignore the, the positive benefits.

NARRATOR: There are many genes that could be put into plants to make them grow better under harsh conditions. For instance, genes that promote salt tolerance or drought control. But despite the potential advantages what really worries protestors about Herrera's work is its capacity to damage the environment. It is a concern held by critics world-wide.

Apart from any health risks, those who campaign against GM have another environmental fear, that the genes from the engineered plant will spread throughout the plant world creating new strains of superweed and superbug we cannot control. First, superbugs. At the moment a third of the world's crops are lost every year as a result of pest damage and cotton is one of the crops most badly affected by the pink bollworm.

GREG WUERTZ (Cotton Farmer): We had a insect problem that was probably costing us between $100 and 200 an acre per year due to one insect which would also trigger other problems for other insects and a kind of a chain reaction for spraying. It causes a lot of damage in the lint and as you see it's inside a boll so it's very hard to control or kill as it's inside. It was just a monumental problem. It was to the point of cotton production was going to stop in the state, I think it was that serious a problem.

NARRATOR: At the University of Arizona Bruce Tabashnik has spent years studying the pink bollworm.

PROF. BRUCE TABASHNIK (University of Arizona): If you have lots of pink bollworm caterpillars boring into your cotton bolls you won't get nice, nice healthy bolls like this one. Instead you get something like this. So if growers have a high population of pink bollworms they won't get a decent yield at all.

NARRATOR: The problem is that because the bollworms burrow all the way inside the cotton boll they're very hard to kill with pesticide sprays. Biotech companies began to devise another solution by introducing a gene into a cotton plant that would kill the bollworms. With an extraordinary irony it was organic farmers who had the answer.

For 40 years organic farmers have been spraying their crops with a bacterium that is poisonous to certain insects, including the pink bollworm. This organic insecticide is called BT. It is not toxic to humans. Monsanto took the insecticide gene from the BT bacterium and engineered it into cotton to give the plant 24 hour protection against the pink bollworm.

ROBB FRALEY: We could take that gene out of the bacterium and introduce it so that a cotton plant or corn plant was now producing this protein in its leaves that it would allow for the plant to control these important pests without the use of chemical insecticides.

GREG WUERTZ: It sounded like too, too unbelievable. It was just miraculous, but we did try it and it does work.

NARRATOR: By planting BT cotton farmers have reduced the amount of chemical pesticides they spray.

BRUCE TABASHNIK: So what it means is they can eliminate about 6 insecticide sprays per year in the areas where pink bollworm was most damaging.

GREG WUERTZ: Sometimes we'd spray every acre with a plane with pesticides and that'd just stay in the air and that was, those things are, I know they're deadly and I just, it's so much better for kids to have cotton where you don't have to spray and you don't put those pounds and pounds of insecticides in the soil, so environmentally to me it's much, much safer.

NARRATOR: But critics say there are potential environmental concerns.

JEREMY RIFKIN: When you place the BT gene into those crops it means that every cell of every plant is producing toxin 24 hours a day over millions of acres and every plant becomes like a little mini-factory producing toxin. The good news for the industry? They'll say you're going to kill a lot more insects. The problem is you're going to kill good insects as well as bad insects.

NARRATOR: It is true that pollen from BT crops could kill insects related to the bollworm, like butterflies. Biotech scientists point out that spraying with chemical insecticides kills both butterflies and a much wider range of non-target insects.

JEREMY RIFKIN: The other bad news? How long do you think it's going to take for all those insects out there to build the resistant strains? You won't kill 'em all and the ones that are left that don't die because they're resistant they reproduce and then you have superbugs against one gene here and one gene there.

NARRATOR: The more a bug is exposed to any pesticide toxin the more resistant it becomes and this is true for bollworms which are exposed to the GM toxin 24 hours a day. The question is: can anything be done about it? This is where Monsanto breeds the bugs that it aims to kill with its genetically engineered plants. They are already a step ahead of BT resistant bollworms. By finding new BT genes from bacteria to engineer into their cotton Monsanto already have new plants to replace the old if the bollworm does become a resistant bug, but so far independent studies on BT cotton have shown that resistance has not yet become a problem.

BRUCE TABASHNIK: We haven't seen that yet, but even in that case it would have meant there were 3 full seasons of protection with a very widely used method and so there are examples with conventional insecticides where they've lasted comparable periods or even shorter periods, so so far it's performing extremely, extremely well, if anything better than expectations.

NARRATOR: But superbugs are not the only environmental fear. These protestors are destroying field trials of GM crops.

(ACTUALITY PROTEST CHAT)

They believe genes will flow travelling from GM crops to contaminate the environment and disrupt and damage the delicate balance of our eco-system and one of the things they're worried about is superweeds.

JEREMY RIFKIN: Those genes will flow and there's no doubt that some of those genes will attach themselves eventually to wild weeds. What happens if your weeds pick up the gene for herbicide tolerance or for pest resistance, they reproduce, they spread, you find out 8 years later that an entire region of the country has a weed that's tolerant of herbicides and resistant to pests. You can't get rid of it, you can't recall it, you can't clean it up.

NARRATOR: The theory is this: biotech companies engineer herbicide resistance into crops, allowing farmers to spray against weeds but leave their crops still standing. But then there's the bee. Protestors fear that bees will carry pollen from GM crops for miles around and transfer the same herbicide resistance to a related plant making them better able to survive and turning them into weeds that will eventually take over the countryside, superweeds.

DOUG PARR: Now in the case of say oil seed rape we know that genes can transfer to wild, weedy relatives. At the moment there's nothing saying it's going to become a big problem, but it could. There is evidence that it will cross, there is evidence that it can persist.

NARRATOR: Phil Dale has to judge that evidence. He worked on the government committee that assesses if it is safe to release GM crops into the environment. He carried out tests to see how genes can spread from GM crops.

PHIL DALE (John Innes Centre, Norwich): I don't believe that gene transfer is intrinsically hazardous. It depends very much on the gene and that is the focus of the risk assessment process.

NARRATOR: To be any danger at all the GM pollen must travel far enough and in sufficient amounts to actually pollinate a weed. The further the distance the less pollination.

PHIL DALE: If you imagine these two plants here at this kind of distance there would be about 5% pollination between them. If we separate these apart the frequency of pollination would, would decrease very sharply. At say 15 metres there will be very little pollination. Wouldn't be impossible, there would be a, a low level of pollination.

NARRATOR: So strategic planning is required. Importantly, although small amounts of GM pollen can travel big distances, it can only fertilise related plants, for example, the pollen from GM rape seed will only fertilise a handful of other plants like the wild turnip, but even if this happens, the plant will only become a superweed if the new gene enables it to compete better with other plants. That's what weediness is.

ROBB FRALEY: The real issue is do these genes really confer weediness properties and there's been, you know, research from many, many scientists that show that, you know, what makes a, a plant weedy is many, many, many genes. It's not a single trait and it's certainly not a trait like herbicide tolerance.

DOUG PARR: These risks may actually be quite small, but we don't know and they're being released into the environment in such a way that they're unrecordable. It's an irreversible step that we're taking by doing so.

PHIL DALE: I'm not belittling the importance and the significance of moving genes in the way we do, but because we're transferring one or two genes we can ask very specific questions about the impact of those genes.

SIR ROBERT MAY: The public in general hear voices reassuring them and voices offering them legitimate apprehensions in some instances about the environment and what I think are extraordinarily exaggerated concerns about food safety, but the public don't have to weight this the way they do the similar contending claims about mobile telephones because there's no clear consumer benefit yet.

NARRATOR: In the developing world priorities are different. While in the West people ask why they need GM food when they already have so much choice, not everyone has this luxury. There are over 100 million children in the world for whom vitamin A deficiency causes catastrophic effects, including blindness. This blindness is caused by a poor diet. These people eat mainly rice and rice has no vitamin A. The only way they can receive enough vitamin A is by costly distribution of supplements that don't reach everyone.

Ingo Potrykus is a genetic engineer who had a brilliant and simple idea. If he would genetically engineer rice to produce vitamin A then this rice seed could be distributed to the poorest areas of the world, he could help prevent this blindness. Potrykus identified the two genes in daffodils that produce vitamin A. They're the same genes that turn the daffodil yellow, but the daffodil is poisonous.

PROF. INGO POTRYKUS (Swiss Federal Institute of Technology): This gene was actually isolated from daffodil which are the basis for the production of vitamin A where some of them make daffodil poisonous so we leave out the poisonous genes, we transfer just 2 genes which help us to produce pure vitamin A.

NARRATOR: Potrykus has now engineered the vitamin A into rice. After testing, he hopes it will feed millions of people around the world preventing vitamin A deficiency and blindness.

INGO POTRYKUS: My entire scientific career has been devoted to this dream to be able to help to solve burning problems of humanity and food security in developing countries is one of the most important problems we are facing for the next decade.

NARRATOR: Critics don't think the high tech fix of genetics should solve the problems of deprivation in the world.

DOUG PARR: I think when you try and, and fix a problem simply by adding another innovation to problems that arise because of political, social, economic problems then you're not going to solve it, you're going to find, find the problem squeezes out somewhere else.

INGO POTRYKUS: To dream of equal distribution of money or food resources world-wide is a nice dream but it can never be achieved. Nobody will have the power to distribute money equally throughout the world. The only solution is to build in vitamin A in their basic food and that's exactly what we are doing for 2.4 billion people and I hope that people who are so far extremely sceptical of this new technique will see that here is an example where this technique has been used for something beneficial for the consumer.

NARRATOR: 25 years ago these scientists voiced their fears about the potential danger of genetic modification causing a health and environmental disaster. Now many scientists believe that a system of checks is in place to prevent this happening and the benefits are real, but there is still a groundswell of public opinion that remains to be convinced.

JEREMY RIFKIN: Is it worth the risk of bypassing thousands of years of classical breeding, putting new GMOs into the environment with genes from unrelated species and then afterwards find out whether it's safe or not. That's the question.

ROBB FRALEY: I don't think any science is inherently good or bad, or safe or unsafe. It's what we do with it, it's how we use it and I believe biotechnology if used appropriately and appropriately regulated has a tremendous benefit. The script will appear here shortly.

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