Note, this transcript should not be copied, redistributed, or quoted without prior permission from the Vega Science Trust. The programme was originally recorded in Spring 1999. 
 

 For thousands of years people have been messing around with plants - to try to make better food. It`s called selective breeding and it`s absolutely the bedrock of agriculture. But it was essentially hit or miss. Hit or miss, that is, until the geneticists and the molecular biologists developed methods to put whatever genes they wanted to, into whatever plants they chose. Genes that could improve their yield, make them resistant to herbicides and pesticides, to mean that less fertiliser might be used.

That all sounds marvellous, on the other hand the criticisms of genetic modification would say that really, it`s science gone mad; tinkering with nature. Newspapers, magazines, even serious scientific journals are full of articles about "Frankenstein Foods" and at the moment the British public, at least two thirds of them, don`t want it. Well is that just because they don`t know enough about the science?

We`ve got five people here today who are going to try to help sort out that question. First of all, Angela Ryan who`s a molecular geneticist at the Open University. David Ho is a plant biochemist and a molecular biologist from Washington University in St Louis, Missouri. Steve Jones, Professor of Genetics at University College, London, certainly one of Britain`s most visible geneticists. Janet Radcliffe Richards, also from the Open University who`s a philosopher of science who`s served on a number of committees concerned with the ethics of science. And finally Dr Mike Bevan, who`s a molecular geneticist at the John Innes Centre at Norwich.

Mike, in a word, where do you stand now on this issue?

Mike

Well, as a scientist who`s been involved in this technology for some time, of course I`m very much in favour of it. What I want to do, is to try and convince people of the benefits that will accrue from the technology, and in doing that explain some of the science that has sadly been missing from recent debates on this subject.

Colin

Janet, as a layperson among these scientists, do you share those concerns of two thirds of the rest of the British population?

Janet

I don`t share them in the same way as the rest of the population because I`m so concerned about the way the debate`s going, and I think it contains all kinds of fundamental mistakes, such as talking about "messing about" and "Frankenstein Foods", and I think that shows all kinds of mistaken pre-suppositions going on. So I don`t know what to think, but I want the debate better.

Colin

Steve, your main interest is snails, do genetically modified plants worry you?

Steve

Yes, because genetically modified plants are an experiment in evolution, and quite a dramatic one, perhaps the most dramatic biological experiment that mankind has ever carried out. We`ve done such experiments before, with insecticides, and with antibiotics, and we`ve had a certain amount of difficulty. My concern is that we`re rushing into this third and greatest experiment without enough forethought.

Colin

David, coming from apparently the more tolerant atmosphere of the United States, what`s your position?

David

I think this is a very powerful technology. It carries a lot of potential, actually some of the potential that we talked about several years ago has already become reality. But at the same time there`s always a risk. So basically my position is, although we have a very powerful technique in our hands, we do not have enough information. So we need to carry out more research to learn more information so that we can better assess the risk in the future.

Colin

Angela, better assessing the risk in the future, or now?

Angela

Well yes, I mean, too early may be too late; we`ve got to do something now. We have to ban commercial plantings, particularly in the UK because we`re such a small landmass. We need to call for a global moratorium, and we also need to fully investigate our future agriculture, globally, and our food security for all people around the world. The GMO issue is the tip of the iceberg really, in terms of that.

Colin

Thank you. Well, from five people then who have already given some thought to this issue, surprisingly divergent views. Everything from the great promise of this technique, to a moratorium now. Let me start with you, Mike, you I think, were one of the founders of some of the technology that`s involved in genetic modification. You come from an institution that`s deeply committed to this technology. Some of your funding comes from commercial organisations that want to exploit it. Could you tell us a bit, first, about the techniques themselves, which I think you know are really a mystery to many people.

Mike

Well, to understand the techniques I just need to tell you a little bit about the genomes of plants, and in fact, most other higher organisms. They contain genes on DNA. Recombinant DNA technology allows you to identify these genes and to move them about - to clone them. Now, it`s possible to clone a plant gene in a bacteria. The technology that started this revolution, as you called it, in our agriculture, was the ability to transfer a DNA from a bacteria back into a plant. Once you can do that, you can transfer DNA from any organism into a plant. This process is called transformation. Now, the trick is to understand how to get genes to be expressed in a plant. A gene is composed of DNA and it`s got two general features. The first is part of the DNA that encodes proteins which go to make phenotypes, or features, and the other part is instructions that tell the organism where and when to express the protein. Without either of those pieces of information genetic engineering doesn`t make any sense. So what we did was to understand what were the two key instruction modules in the plants, what made a protein and what made a protein express at a particular time, and put that into a bacterium. Now this bacterium is called agrobacterium, and it has the natural ability to transfer its own genes into plants, and thereby cause a disease. What we did is to stop the disease causing aspects of this gene transfer and replace the disease causing genes with genes that had, from our point of view, some scientific benefit. Once that work was carried out, then of course it became clear that you could transfer any gene that you wanted into plants. This big interest in this technology has now taken off.

Colin

And have those benefits really emerged? What would you point to as the major successes so far of GM technology?

Mike

There are two major successes that are, I think, good examples. The first is the use of, in cotton, of a gene that makes the cotton resistant to the Bole weevel. Cotton is a very important commodity crop of course, we`re all wearing cotton. However, it is very very environmentally damaging to produce, in terms of fighting insects. The introduction of the BT gene in cotton has resulted in a substantial reduction of the use of toxic insecticides in the Mississippi Delta, where nearly half of the cotton plants that are grown are GM. The corollary of this is that there is now a wider variety of insects growing in cotton fields in the US than there were before, because of course this insecticide engineered in the plant is specific for the bole weevil, whereas previously the insecticides killed literally every insect. The other benefit that has come out of GM crops has been the use of herbicide tolerant plants. This promotes the use of safer, more environmentally benign herbicides, and greatly improves the quality of the soil, because previously if you were growing Soya beans you might have had to drive your tractor across the field five or six times, to weed, etc. Nowadays you drive your tractor across the field much less so there`s less energy inputs, less soil compaction.

Colin

Steve.

Steve

I think we have to realise what a powerful technique this is. It is only, to be frank, 20 years ago we couldn`t possibly have contemplated of having this conversation - it would have seemed like real Frankenstein stuff. And it`s happened. Let`s take, for example, the cotton story. The reason that cotton has to be sprayed so often with insecticides is that insecticides have been abused to such an extent that all the insects have evolved resistance. That`s why they need these BT plants. In fact, the only reason that cotton is grown in the Mississippi Delta is that the farmers are subsidy junkies. It`s not economic to grow cotton there. They live off the subsidies. So what we`re basically doing is using another technology to fix a problem that came from our first technology. Now that, I have to say, doesn`t make me very hopeful about the use of this technology. It`s a fantastic technology - the things it can do are far more astonishing than anything we`ve heard so far. But we`re using it to promote an agriculture industry which really doesn`t pay without governmental help, to help it escape from the problems it`s made for itself by using the previous biological technologies so badly.

Colin

Yes. David, what do you feel about that?

David

I think that these two examples are very good examples, but I would like to address a little bit more on this herbicide resistant Soya bean. I think this is probably the better of the two. Soya bean has been a major problem in the United States. The United States has been exporting Soya bean to many other countries, so Soya bean yield has a major impact on world food supply. So why herbicide resistant Soya bean is good, is because the traditional herbicide we normally use, are proven to be nasty. It carries a health problem, it`s not very effective. And Rhonda (this is a low risk herbicide whose resistance has been engineered into the Soya bean), this one turns out to be probably the best herbicide. Of course, probably the best way to do it is to not use herbicide at all, but if you have to use herbicide, this is probably the best one. The farmers, actually, have been telling us a successful story. That is, 30% of the American farmers are now using Ronda, that`s the name of the herbicide, Ronda ready soda bean.

Colin

Yes. Janet, were you reassured by what Mike had to say?

Janet

This is just the kind of debate I want to hear, because it tells me more of the details of what`s going on, and what the risks are. I`m concerned with the general aspect of the discussion which says, "here is a problem caused by our technology, we`re solving it with another bit of technology". It seems to me this is the whole history of the human race, is anybody going to suggest we go back to not having technology, and if so, where do we go back to? I don`t think it`s true that technology is in itself dangerous, it`s a question of what it does. This is where the debate worries me, because I think a great deal of it seems to be focused on the idea that we`re meddling, and meddling is a bad thing to do. I think that presupposes the idea that the universe would be nice and orderly and comfortable if only we let it alone. Whereas post-Darwin, we know very well that it isn`t.

Colin

OK Angela, we`ve always been meddling, there haven`t been major disasters before, it`s our only solution to our problems to continue to meddle. Would that be your view, or not?

Angela

Well, I`m afraid that my view is that genetic engineering is a new departure from conventional breeding. The vectors that you discussed -

Colin

What`s a vector?

Angela

A vector is an invasive genetic element, and genetic engineers are making chimeric vectors from natural invasive genetic elements. Horizontal gene transfer, lateral transfer of genetic information and material is widespread in nature. We`re finding more and more examples, particularly among bacteria.

Colin

You mean that genes which have been engineered into a plant can spread to other plants in various ways.

Angela

Yes, my view is that if you can get the vector in, you can get it out again. Integrase is often used we know that it has disintegrase activity in vitro. I think that we`re at the beginning of our understanding of these genetic invasive elements. We know that there are barriers out there in nature to them: there are genetic barriers, there are introduction barriers, establishment barriers and there are various things that occur. Genomes are able to recognise when they have been invaded and there are post-transcriptional gene silencing mechanisms. In fact, the BT toxin cotton transgenic line has failed in America because of post-transcriptional gene silencing.

Colin

You`re saying here that the plant that is modified to be benefited in some way, reacts to the process of genetic modification, in ways that are disastrous, or can be, potentially.

Angela

Yes, it can happen at any point in time, as well.

Colin

And what kinds of thing can go wrong? Changes in the yield, or?

Angela

I mean, they fail! You spray the herbicide on them and they`re no longer resistant; they die, and then you`re into litigation. With law suits and everything like that, which has happened already in America over the BT toxin in the cotton.

Colin

You talk about a moratorium. Don`t you think that the kinds of safeguards that have been set up already are adequate?

Angela

No, no I don`t. I think that we`re at the beginning of our understanding of gene regulation as well, that`s another aspect. You insert the vector in, it goes in randomly. In order to get transcription it has to land in a site of active transcription. It can also land in a site of redundancy, where genes are not being transcribed, it can also land there as well. We also know that the genes which are redundant have a role to play in gene regulation, and that the packaging is the message now. We`re beginning to see that the structure of the chromosomes is crucial to gene regulation. I would argue that your vectors are imprecise, they insert randomly, and there may be problems with the gene regulation of the plant that are unpredictable at this point in time.

Colin

Are genetically modified foods dangerous to us, who eat them?

Angela

Well, there is no answer to that, because we haven`t done enough feeding trial experiments with genetically modified foods. Pushtai was the first scientist to really investigate this, and I know it`s a controversial area. I think, again, more science needs to be done. But yes, DNA fragments have been found to resist digestion in the gut and have been found in faeces, and found in tissues of the body as well. So there`s no guarantees that it is safe.

Colin

OK, so you`re saying there are risks for the plants that are modified, for the rest of the environment, and conceivably for the consumer as well. What do the three of you think about this?

Steve

There`s a strange sociology of science about this whole story. The question of whether or not these things are safe to eat is actually a rather simple scientific question. Anyone of us, any one of the general public could design the experiments that tells you whether or not they`re safe to eat. I`m certain of one thing, which is that I`d far rather eat a diet based only on genetically modified Soya bean than eat the average Scottish diet, let`s say, which is hamburger, chips and egg. Now we know that`s bad for you, that is definitely bad for you; nobody worries about that. So I think that the danger of eating these things has been greatly overstated. The difference between that kind of thing -

Colin

But if I can interrupt you Steve, the difference is that you can actually stop eating eggs and chips if you learn enough about them. We face the possibility of having present food supplies being replaced to a very large extent by genetically modified foods, and essentially having no choice.

Steve

Now that`s not a scientific issue, that`s an issue of marketing. If the public refuses to buy this stuff, it won`t succeed. It`s very noticeable that the first couple of allegedly highly successful genetically modified crops like the tomatoes just failed, didn`t pay.

Colin

Are you happy with that, Janet?

Janet

The thing that worries me about it is that if things which have been genetically modified are going to be harmful, it isn`t because they`ve been genetically modified, it`s because of the particular thing that`s been done to them. The trouble with the public debate is that it makes it sound as though genetic modification as such is a dangerous thing. That we need to find out whether genetically modified foods are bad for us, and if they are, they will be so individually. This is what makes me think that the debate is propelled by a fear of interfering where we ought not to be interfering, rather than a concern for the individual foodstuffs which, as Steve was saying, you want to test from all kinds of points of view. Genetic modification from that point of view is neither here nor there.

Colin

David, has Angela given us a fair view of the risks?

David

I want to echo what Janet just said. Genetically modified products cannot be considered as a common group of products. We have to look at individual cases very carefully. The thing I worry most is not whether the gene will hop out, because of the sequences we use. Actually I don`t think this is a serious issue any more because we have other means to transform plants. The thing I worry about most is the out-crossing of genetically engineered plants with other plant species. For example, I`ll give you a scenario, although we really do not know very much information about it. Soya bean pollen could cross with plants which are very much related to Soya bean. What happens if this herbicide resistant Soya bean pollen crosses with another plant which is very similar to Soya bean. Then we generate another herbicide resistant plant. That could be a concern.

Steve

That`s really my major issue. We always used to think of species in a sort of platonic way. That they were an essence, didn`t cross, and in some ways Darwin himself pushed that idea. Now we know that, particularly in plants, and to a surprising extent in animals, that`s not true. And indeed, for example with oil seed rape in Britain, there is hybridisation between oil seed rape and wild plants. I happened to be speaking the other day to somebody who is working on the science of this question for a British government organisation, and I`m sure she was a first rate scientist. I simply said, well, what happens if this stuff gets out into wild beets, and the answer was - it actually gave me rather a chill - she said "There`s always another herbicide". We know from our own experience with antibiotics that isn`t true, now there aren`t any more antibiotics. We may get away with this for a while, but what happens when we stop getting away with it. And I think that`s the crucial question, how much hybridisation is there going to be.

Mike

There`s another question that you have to answer before that argument has legitimacy. Until now has there been any concern about the crossing of agricultural species with near-wild relatives - there`s been no concern. There`s been no concern because it doesn`t matter a damn.

Steve

But until now we haven`t been putting engineered genes into the agricultural plants, we`re in a different kettle of fish now.

Mike

Yes, but outside of an agricultural context these genes have no selective advantage, they -

Steve

You seem very confident of this fact, how do you know?

Mike

Well no, I`m really puzzled by why this is a problem.

David

But now in this case since we have this herbicide resistant gene, so this would give the other species, the other plant -

Mike

Farmers don`t use herbicides except in the field, they drive their tractors up and down. If a herbicide resistant gene is in the hedgerow -

David

Yes, but what happens if the seeds landed in a Soya bean field, then the seed will have a better chance to survive, so we do have a selection.

Mike

That`s what we call agricultural practice. That`s the whole point of these studies that are going to be conducted in the next few years in the UK, is to work out the best practice for these things, in the UK agricultural environment.

Colin

Let me just try and rehearse what, as I understand it, some of the worries are. They are that the genes themselves that are put into plants might become toxic in their host plant. That they might encourage the plant to produce toxic or allergic substances. That they might even reawaken viruses or other agents that were dormant before, and that they could potentially spread, and that seems to be a major concern, to other plants and have a wide ranging impact on the environment. Now, Mike, convince me that it couldn`t potentially be dangerous.

Mike

I think that you`re asking a very difficult question that can only be answered by extensive trials. Now, I want to convince you that these trials have been conducted, in the case of herbicide resistant Soya bean for example. These experiments, the original experiments, were done twenty years ago. It`s only now, after exhaustive tests on the agricultural performance of these plants, where key features such as stability of the trans-gene, the heritability of the trans-gene, and all sorts of toxicity studies that are published, and are part of submissions to the food and drug administration and other authorities in the US, all of these experiments have been done. They are good enough to convince the American public, that this particular crop, with this bacterial gene that detoxifies this herbicide glyphosate, poses no recognisable threat to humans.

Colin

David, the American public are convinced, certainly more convinced than the British. Is it the quality of their reading of the science that`s done that, or what else is behind that? Are they just more knowledgeable?

David

This remains an open question. I don`t think we have the answer. The company pushing for this kind of product, in this case Monsanto, certainly is not doing a superb PR job, so I don`t think it`s because of their PR job. But somehow I think that the economy is driving the introduction of genetically engineered products. Again I want to mention this Ronda ready Soya bean because Soya bean is so important in our American agriculture. And now the farmers are joining force with Monsanto. It`s not because they are bought by Monsanto, it`s because they see the value of this product. So Mike`s point is very important. If, in the future, Monsanto is not charging the farmers for this additional fee for using this kind of seed, farmers will be able to sell their agricultural product with even lower price. Then the consumer will really see the benefit. Now at that time, I would say, this is my prediction, not only the American general public, will be more interested in using this kind of product. People from other countries will probably join them.

Colin

So you don`t believe there`s any toxicity risk at all in this process?

David

So far there`s no proven one.

Colin

But have there been adequate tests to know?

David

For Ronda ready Soya bean, I would say yes, there has been adequate. For other things I cannot say for sure. So that`s the reason I emphasise that we need to study case by case.

Colin

And the Monsanto studies on toxicity have been published?

David

Has been published. Has been, not really published all in scientific journals, but they are publicly available information.

Colin

Ah but that`s just the kind of thing that we hear Pushtai`s work criticised for, that all we have are public statements and not peer-reviewed papers.

Mike

We don`t have a constant drip-drip of little pieces of information like we`ve had from the Pushtai thing, companies cannot of course work like that. The data obtained by Monsanto - and of course other companies, we mustn`t keep banging on about Monsanto, they`re not alone in doing this, they`re not the biggest company doing this either - It`s important to realise that all of this work is publicly available. Some of it that`s relevant is published in peer reviewed journals. Most of it is just screeds of toxicity data, that are available. OK, but I think you asked me a very difficult question for a scientist to answer, and that is, can you be absolutely safe about something. I think we ought to look at a normal Soya bean that we would eat, you can get it from Iceland, you know it`s not GM, and a GM modified Soya bean, and compare their behaviour. Toxicity and anything else should be looked at relative between a normal Soya bean and a GM Soya bean.

Colin

Would that reassure you Angela?

Angela

No it doesn`t, because I`ve looked at some of these datasets that are available in the public domain, and the thing that worries me is that molecular analysis to confirm the stability of the transgene, is not there. I don`t find in-situ work over generations, I don`t find southern blots ???? over generations -

Steve

I think you`re being terribly rude to Darwin here. Let`s go back to this issue of insecticide resistance. As I`m sure you know, houseflies are resistant, all over the world, to a particular insecticide. And it started becoming so about 15 to 20 years ago. Now if you look at the DNA of that gene, and the bits of DNA surrounding it, it turns out that every single one of the, I suppose hundreds of billions of houseflies in the world, all carry exactly the same gene. So the accident only took place once, it only has to happen once, and it can spread. Now I don`t know any lab test that can say this isn`t going to happen. It`s a different kind of risk. I`m with you in saying, I believe this stuff is safe to eat, and if it isn`t, we`ll very soon find out. But as an evolutionist I know that evolution turns on rare events, unexpected events. If we`d been having this conversation about, say Penicillin, in 1948, people would have said "You`re mad! Penicillin works wonderfully!" Fifty years on? It`s almost gone. That`s what worries me.

Mike

The purpose of this debate is to try and establish some basic facts. You talk about evolution of blow flies. Of course, that`s terribly interesting, but blow flies don`t live in an agricultural environment. Every year a farmer puts out seeds, and he takes seeds back, and he destroys what`s left. It`s like a painter coming in and painting a new canvas every year. It`s not a population of organisms you put in and then hey, let`s see what happens.

Steve

That`s not really true. Every single agricultural plant and animal is a pest somewhere in the world. There are pest carrots out there, pest horses in the deserts of California, so we really have to think like ecologists here, not like toxicologists. And I`m not saying that this technology is necessarily bad, and I think it`s a very crucial point that we shouldn`t say that GM itself is bad, it`s what you do with it that concerns me. It`s a classic example in the Guardian newspaper which I read, although it makes me grind my teeth. A few weeks ago they came out with a piece that said that they`d fed GM foods to an insect, which had been eaten by a ladybird and the ladybird died. But what was in the damn food? It was some powerful poison, no wonder the ladybird died. I wrote to the editor saying that this is like, somebody commits suicide by drinking a wineglass full of cyanide, so you ban wineglasses! I mean it doesn`t make sense, we have to think in a mature way about this. But I`m still worried about this medium to long term problem - do we need to do it now?

Janet

Now the medium to long term, and the evolutionary one. Everybody knows since Darwin, or they should, that bugs are going to adjust themselves to whatever toxins you throw at them, and suchlike. But the question is, should we not have done that in the first place. Are you saying we shouldn`t have used the insecticides?

Steve

No no no, I`m not saying that at all.

Janet

We know that evolution is an arms race.

Steve

Certainly not. There was a piece in the British Medical Journal a few weeks ago, several articles together, an excellent little compendium about antibiotic resistance, and they used the word "criminal insanity" about the way that antibiotics had been used, and are being used, for example in Africa. If we`d known what would happen, we would`ve used antibiotics in a totally different way, and we`d be much better off. And that`s my concern, an unformulated one, about GM Foods.

Janet

But could we have known in advance?

Steve

I think the answer to that is, yes. Maybe we couldn`t then, now we do. We know what can happen. We ought to be more careful.

Colin

Can we just talk about one of the major concerns that`s been very widely aired, in the popular media, and that is this possibility that genes deliberately inserted in plants to improve their quality, (a) might fail in those plants, and secondly might spread to neighbouring plants, weeds for instance, and confer on them the very qualities that we`ve been trying to engineer into the plants we want to save. Angela, what`s the risk of that?

Angela

Well, it`s already happened in Britain. The oil seed rape has outcrossed, and carried herbicide resistance with it. But I`d also like to bring up the point that antibiotic resistance, in the presence of antibiotics, horizontal gene transfer can increase ten to a hundred fold, and that`s probably why it spreads so rapidly, the antibiotic resistance that is. Now we`re using antibiotic resistance in these plants as marker genes, and it has been said before that they ought to be - it`s very difficult to remove them once they`ve integrated into the recipient genome -

Mike

I wouldn`t have said that, the DNA is really unstable.

Angela

Yes, no what I`m saying is that if the antibiotic resistance genes used in GM, manage to escape and get into soil bacteria, for instance,

Mike

That`s where they came from, for gods sake.

Angela

Well that`s what I`m saying, if they return to soil bacteria, and in the presence of an increased level of antibiotics in our general environment, because the misuse and abuse, that you [Steve] have mentioned, then we`re again releasing more and more anti-biotic resistant

Mike

These anti-biotic resistance genes are already, they`re ubiquitous, they are in every gramme of soil and every breath of air that we breathe.

Colin

I think we need to know something first, I think people will be very confused, with the notion that you`re trying to get a gene in to a plant that makes it resistant to herbicides, and you have to use an antibiotics resistant gene as well. David, could you clarify that, what exactly is going on?

David

In transfer technology you need to have this marker gene, which usually is an antibiotic resistant gene, in order to select the transformed plants. But this antibiotic resistant gene does not have to stay in the transgenic plant. There are which allow the scientist, although it will take a bit more effort, to take the marker gene away. So I don`t think this will be a serious issue in the future. Also those special genes, so called marker genes, are not really that important because the antibiotics that we use in sylaptane, are not really important antibiotics for human use.

Colin

So let`s see if I`ve got it right. You put a marker gene in, which confers antibiotic resistance into the plant, when you`re generating these things. So you can then sort them out from the rest that haven`t got the transferred genes, by applying antibiotics to them, which kills the rest. And now we`re worried about the consequences of the antibiotic gene that`s been produced as a marker. So it can be removed?

David

Yes, you can remove that. Techniques are readily available to remove the particular gene. So once you have the transgenic plant, you can take the marker gene away, so the only gene you have, for example if you talk about, Glamphosine resistant Soya bean, the only thing that you will have will be the glamphosine resistant gene, nothing else.

Colin

You also have a promoter, don`t you? Can you tell us about promoters?

David

Promoters basically are a regulatory unit of a gene. In order to turn on or turn off a gene properly, you need to have switches, just as we have switches for the lights in the room. You need to have those things. The promoters basically do not encode any protein, so those sequences do not generate a protein of unknown function.

Colin

But if I understand correctly, they could conceivably influence the expression of other genes in the host plant, for instance, isn`t there evidence that introducing genes into some plant species changes many other aspects of their metabolism, the protein levels and so on; that they produce, other aspects of how they function. It`s not as clean as it sounds, this technology, is it?

David

It has happened. But the experiment could be done in a very careful way. When the genes are inserted, of course there is a randomness of insertion. So you generate many different lines of transgenic plant. If I was running a company, I`m not going to release all of those lines, I`m going to select the lines with the insertion at the proper place. So there`s a difference between a good bio-tech company and a not very good bio-tech company!

Colin

Angela, how easy is it, do you think, for the selection that David`s talking about?

Angela

Well yes, you end up with one plant after a lot of work. It`s not easy to produce these transgenic lines, let`s face it. But the problem is that the most abundant promoter used is the cauliflower mosaic viral promoter. Now it was revealed in 1990 that the actual promoter site is a hotspot for recombination in the virus. It is also not really specific, it`s a para-retral-transposon viral promoter, it is related to Hepatitis B and also to AIDS, which is a retrovirus. One must remember that these sequences are not really specific, and as it`s been demonstrated that it`s a hotspot for recombination, so it`s an open door.

Mike

Nevertheless, if it was really a hotspot for recombination, and increased the rate of recombination significantly, then of course the transgene would be unstable.

Angela

You don`t know that, because a lot of the molecular analysis isn`t done over generations, so you can`t -

Mike

Of course it`s done over generations.

Angela

Well maybe in your lab, but not in others, I can assure you of that.

Mike

No, I have to try and clarify and get some facts on the table here. You do a transformation experiment, as David said you get hundreds and hundreds of transformants. Some of them are deeply disturbed individuals, so you chuck them in the bin. You find one or two that perform according to expectation, you take them through, you look at genetic stability, over many many generations, and you choose the ones that behave as you want. This is normal agronomic practice. You don`t just go into the lab, bang something into a plant, and a few weeks later chuck it out, and it`s progeny, out in the field. There`s an enormous process that goes on, for every agricultural plant, GM or non-GM plant, that goes out there. So these issues...

Angela

So then why is that data missing from the datasets in the applications?

Mike

Perhaps because it`s been published elsewhere at an earlier time.

Angela

Well it`s all meant to be accumulated in one great big document. These applications are all - they`re just not there. I agree with you -

Mike

Companies do not want to spend hundreds of millions of dollars on a product that is unstable, it`s not in their interests.

Angela

They`re very expensive experiments to do, and I can understand why they`re done in the beginning but not over generations, but the thing is that - you know, you`re right, if you can do analysis over time and demonstrate that it`s stable, then that`s fine. But my worry is, why isn`t it done in all cases. It`s not, and that`s my concern. What goes on in good labs is good science, and what goes on in labs that are more married with business is cutting corners and -

Mike

I actually think that scientists who work in business have got far much more to lose by doing bad science than academics scientists. Academic scientists, we can afford to be sloppy from time to time, it just means our paper`s not getting published in "Nature", it`ll be in some less prestigious journal. A scientist working for a company, their science has to be of the highest and most enduring value, because they will get -

Angela

Well I disagree with that - well no, they`ve got to get over the regulation, they`ve got to get through the regulations, that`s what they`ve got to get through.

Mike

There`s no logic in your argument. They work with the regulatory authorities. It`s not as if there`s some life science company trying to foist a toxic population of plants on us, unsuspectingly. That is a dreadful image!

Angela

I don`t think that! But what I`m saying is that the regulators are involved very closely with the industry, and the regulations are set with these negotiations between the industry and the regulators, and what I`m saying is that that relationship is dangerous, because it means that you can get these products onto the market without the same stringency.

Mike

I agree, if there`s a perception of that, then perhaps later in the discussion we can come onto how the regulatory process can be made more open and bring in a wider, a variety -

Angela

A much more independent, scientists involved in the regulation would help a lot.

Mike

No, I was thinking more about environmentalists, and consumer bodies, who would bring a new perspective.

Angela

Absolutely, yes, I think that would be a very good idea for the future.

Colin

David, you live and work in the same town as the headquarters of Monsanto, how would you like to be a scientist employed by a company who`s told to engineer a plant so that it will be infertile and it`s seeds can`t be collected by farmers in the third world, and planted again; that`s being done, isn`t it?

David

Yes.

Colin

What do you feel. I mean, would you be happy as a scientist to work in that kind of programme, beautiful though the science may be?

David

This is an interesting question, Colin. Actually in university involvement, sometimes we pursue the same type of research, maybe the final goal is a little bit different, but we want to study why certain seeds are fertile, and other seeds are not fertile. We also want to understand the longevity of pollen, we also want to understand the development of pollen, so the only difference is the very final outcome, in that case its application.

Steve

You know, I hate to speak out for the GM industry here, well I don`t actually, they do some very fine science. I think we have to remind ourselves just how much success genetics has had. The example I always think of is India. Now in India there is, quite understandably, a lot of concern about genetically manipulated plants, particularly the so-called terminator technology that means that farmers can`t plant their seeds next year. India now, for the first time probably for 500 years, with a massively increasing population, is a net exporter of food. And the reason it`s a net exporter of food is because of agricultural technology, largely. Partly genetics, because we introduced genes by ordinary crossing, in the 1950s and 60s, partly agribusiness. Many of the peasants may indeed have gone out of business, and that`s very sad, but the net result is, the greater good is, that India now makes not only enough food to feed itself, but to feed some neighbouring nations too. So we have to remember that, and that is the promise which GM foods brings. So I`m by no means completely against them, at all. What I am worried about is this gathering rush into using GM foods, to increase the profits of companies - nothing wrong with that - in the worlds richest economy, which normally has a huge surplus of food, which would solve its problems not by eating more beef fed by Soya beans, but by changing its diet. We all want to sit and think "what are we doing?" somewhat more carefully, because what this technology can do is mind bending. I mean, we haven`t mentioned some of the things, I mean things like growing human proteins in potatoes, things like a vaccine against diarrhoea, which children might be able to eat in the third world simply by eating a banana, things like salt tolerant rice we could grow rice on sea shores, never been done before. Fantastic technology. Why rush into it so quickly just to increase the profitability of the American agriculture sector, that`s what worries me.

Colin

Mike, can I ask you a question. You`re very confident about the methods, about the science, about the control of risk and so on, and yet your views are opposed by, not just by some of the tabloid newspapers, or those in general who are opposed to science and its efforts, but by serious scientists, well qualified scientists. What`s wrong with their scientific arguments?

Mike

I think it`s actually very easy for people to find common ground in these issues. There are a multitude of reasons why some scientists are against it, you`ve heard an argument from Steve that takes a point of view that the science is fine, it`s got great prospects, I agree with those views, but he`s concerned about the role of corporations, and agriculture. That is a separate issue, and that`s part of the political environment that we live in. Perhaps it would be best if we went back to the good old days of having state sponsored plant breeding.

Steve

That isn`t really what I was saying. You may not like these corporations but they`re inevitable.

Mike

They`re inevitable, but because they are driven by capitalist concerns, they need to make a lot of money quickly, basically because they`ve spent an enormous amount of money on the promise of this technology and they want to recover it. That I think accounts for the very dramatic speed of introduction of these things.

Colin

So you`re saying there`s no scientific merit in the criticism of GM technology?

Mike

Well I think we need to look at it in a case by case basis. What I`m saying is that the process of genetic manipulation itself is not inherently dangerous, it is merely an extension of plant breeding practices where we use single genes instead of a large number of genes. Of course you can make toxic plants, Dr Pushtai made toxic plants, that`s very clear, but Monsanto doesn`t want to make toxic plants, for goodness sakes, it`s in the business of making nutritious foods for us. So I think it`s very difficult to answer your question in general. I think the process itself is proven to be suitable technology, what genes you put in, we have to look at the benefits, or otherwise, of each of those in turn. And I think that the first couple of examples that were given, particularly herbicide tolerance, there are clear benefits to farmers for using it. There are no benefits to the consumer, unless the product is cheaper, and that accounts for some of the consumer resistance to these products.

Colin

Mike, if you were forced in this grouping, to give advice to the politicians about what they should do next, what would it be?

Mike

Well I think they`ve made some very reasonable steps. First there is going to be a period of three to five years I think, in which no commercial growth of GM crops for commercial use is going to be permitted. In that time there will be an accelerated research programme to look at the environmental effects of particular GM crops, the ones that are most likely to be first introduced into this country, to look at the environmental effects of the introduction of these plants. If, during the course of that time, any of these GM plants are shown to have an unforeseen effect on the environment, then of course they won`t be allowed. But for that process to happen we have to increase the range of people who have a stake in the decision making. We need to get consumer groups on board, we need to get environmental scientists and environmentalists themselves involved in these processes. That`s a key meeting ground I think.

Colin

Janet, is that good enough?

Janet

The point about risk and scientific advance is that you just cannot predict what`s going to happen. Things keep taking us by surprise, we didn`t know that aerosols were going to start messing around with the ozone layer, and so on. Anything can take us by surprise, so I think we should work on the principle that we don`t bring in these things which could have large repercussions unless there`s a good reason for doing so. Now I take it with GM foods there are some good reasons for doing so, and I think the mere possibility of harm is not a good reason for opposing what we know to be good. But it might be a reason for being cautious with things that we don`t know to be good. And I say this on the basis of the fact that in the whole of the history of science, every time people have come up with a new advance, people object, they worry about going against nature, and they invent all kinds of harmful effects which hindsight shows don`t happen. Anyone can produce unexpected bad effects, but look at all the bad effects which people predicted which haven`t happened. People still resisted them. I don`t think there`s a clear rational way except to say if something obviously does some good, you need a good reason for opposing it.

Colin

Steve, committees of experts, with lay representation and more research, is that good enough?

Steve

Well I`ll go on as a layman... Yes, that`s obviously called for, and the point that has to be made is the different kinds of risk. We can find out whether or not these things are dangerous to eat, quite soon. My guess is they will turn out to be perfectly healthy to eat. However I do have this lurking fear that we`re fiddling, not with physics, but with biology. And you can work out the risks in physics, for nuclear power stations, and so on, quite well. Biology isn`t like that, evolution is a machine for making the almost impossible. When an engineer designs a bridge, or a power station, he doesn`t expect the power station to fight back. And evolution can fight back. This is our third biological experiment: insecticides, antibiotics, and now this, the most powerful one, the most amazing one. What are we going to do if it fights back? I`d like to know a bit more before we get into the battle.

Colin

David, do you think we`re taking the right approach in this country? How is it different from the States? Are we doing all we need to do to reassure ourselves?

David

This is an international issue, so this is not an issue of the UK, it`s not an issue of the USA, because our involvement is the same as your involvement. So different countries are following different approaches, but by and large we are doing the right thing in my opinion, that is the scientific community is actively engaging the general public, like what we are doing now. The science is moving so much faster than the general public could catch, if we do not actively engage the community, the general community, they will not be able to know about what is happening. Any time there is a new technology developed, the society in general is very anxious. The development of antibiotics, vaccination, all follow the same history. I remember seeing a cartoon, people believed they could have a cow`s head, or a cow`s something coming out when they are vaccinated. And obviously that`s not true. So this is the responsibility of all of us, to educate, or to engage the general public.

Colin

Angela, are we doing enough to engage and educate, and have we got the science under control?

Angela

I dread to think of the idea of gene smog, in ten, to fifty, to a hundred, two hundred years from now. It really does worry me that this is a possibility, and we can do the experiments to find out, and we must answer the unanswered questions, and we need more research. So yes, a moratorium is essential, and I think the government has done the right thing by stopping the commercial plantings of these crops. Doing the research, doing the homework properly. Only then can we be sure that we`re not going to end up with gene smog. Your point is very true, it`s a global issue, and there`s no point in us stopping it, and France going ahead, or Belgium or wherever, because the pollen`s going to blow over! It`s a global issue, and it`s an international effort. It may well unite the world, in a way we`ve not seen before.

Colin

Well there we are, I think the one thing that we`re all agreed on is that more research is needed, and that there`s a need for more transparency from scientists in what they`re doing. David put his finger on it, that it`s not good enough anymore for scientists to say that they know best, and to leave the public behind. We have an enquiring, inquisitive, concerned public, and it`s the responsibility of scientists to inform them, not only about why they do things, but exactly what it is that they do, and what the potential risks are. Thank you very much for helping us to start that process.