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Date:

July 11, 2000

Subject:

GENETICALLY MODIFIED CROPS: DEMYSTIFYING THE SCIENCE

 

Times_New_RomanGENETICALLY
MODIFIED CROPS: DEMYSTIFYING THE SCIENCE

given to the RSA (Royal Society for the encouragement of Arts,

Manufactures and Commerce) in UK


Professor Derek Burke

Cambridge, UK


1. Introduction


Times_New_Roman1.1.
Let me first tell you what biotechnology is. I shall define it as "the
application of biology to human use" and then distinguish, in this
broad definition, "old" from "new" biotechnology. By "old
biotechnology", I mean a series of technologies that have been in use
since we ceased to be hunter-gatherers. These include:

Symbol
Times_New_RomanFermentation,
for the production of fermented drinks, such as beer and wine, and
foods, such as bread, sauerkraut and such delicacies as Swedish
fermented herrings!

Symbol
Times_New_RomanPlant breeding,
extending from the dawn of agriculture, in the breeding of corn for
example, right up to the present day, in the production of modern
high-yielding wheat strains, for example, the short-stalked varieties.

Symbol
Times_New_RomanThe use of
enzymes in food processing, for example the use of an extract of the
calf's stomach (containing the enzyme chymosin) in cheese processing.

Then there are a number of 20th Century developments, such as:

Symbol
Times_New_RomanA fermentation
process for the production of acetone, for use in explosives, developed
during the first World War.

Symbol
Times_New_RomanAnother
fermentation process, using deep vat fermentation, that was developed
for the production of penicillin in the Second World War.


1.2. But "new" biotechnology derives from techniques discovered only in
the last 20 years. Briefly they are:

Symbol
Times_New_RomanThe ability to
cut and stitch DNA.

Symbol
Times_New_RomanThe ability to
move DNA and genes from one organism to another and moreover the
ability to persuade the new gene in this new organism, that is to make
new proteins.

Symbol
Times_New_RomanThe ability to
modify proteins by a process termed "protein engineering".


1.3. DNA is first cut up by the use of a class of specialist enzymes,
called restriction enzymes, which cut DNA into gene-sized pieces. The
mixture of pieces is then forced into bacteria, at an average of one
piece per bacterium, and then these so-called 'transformed bacteria'
are grown up, on ordinary agar plates, so that each single bacterium
grows to form a single colony. Each bacterium in the colony will be
the same as all the others, that is the colony is a clone - like a very
large number of identical twins! Most of the clone will contain a
single one of the gene-sized pieces, although some will contain none
and some two or three. There may be several million of them and
somewhere in there is a bacterium with the gene you are hunting for!
Or maybe only part of it, because the restriction enzymes can cut in
the middle of a gene. But this process has achieved three things:

Symbol
Times_New_RomanIt has broken
the DNA down into gene-sized pieces,

Symbol
Times_New_RomanIt has separated
them from each other, and

Symbol
Times_New_RomanIt has turned
one molecule into millions, and given the scientist enough to work
with.



1.4. The next part is the hardest: finding the right gene. It is just
like trying to find a needle in the haystack and it is hard unglamorous
work! It is called 'screening' and involves testing the DNA extracted
from individual clones, or more commonly, from pools of clones, for the
gene you are searching for. Once you have the gene cloned, then the
precise sequence of the DNA can be determined by a mixture of chemical
and biochemical techniques. Finally it is possible to reinsert any of
these pieces into another organism, which does not have to be a
bacterium, but maybe a plant or animal cell. So genes can be isolated,
their structure determined, transferred to other organisms and,
crucially, made to work there. This is possible because, rather
broadly, the way genes work is universal, from bacteria to man. These
two techniques are what is called "genetic engineering" or "genetic
modification".


1.5. Over the last twenty years, we have learned how to isolate any
gene from any living organism, introduce the new gene into another
organism, and get it to work there, and because genes
work in almost the same way in all living organisms; it is incorrect to
speak of a human gene, or a fish gene etc. The gene is a human gene
because it is functioning in a human cell, not because there is
anything about its structure or its chemistry that is basically
different; an important point that lies behind some of the current
confusion. Indeed genes from different organisms may be very similar
to each other; the insulin genes, for example, only differ marginally
between fish and humans.


1.6. So genes can be isolated, and their precise structure can be
determined. A typical gene consist of about 1000 units strung
end-to-end in a precise sequence, with one of four possible building
blocks at each position. This part of the gene is called the coding
sequence because it determines the sequence of the product - the
protein. So we have the central dogma of molecular biology: 'DNA makes
RNA and RNA makes protein'. Genes also have switch signals at either
end, to switch the gene on and off. The 'on' switch is called a
promoter and they do differ, not only between organisms but within an
organism. For example, plants have specific promoters, so that starch
is made in the tubers we call potatoes and not in the leaves, although
the genes to make the starch are present in every cell of the plant.


1.7. Once the structure is known, the gene can then be made
synthetically - that is put together in the correct sequence from the
building blocks. And variants of the gene can be made too; these will
make different proteins which may be more suitable for what we want to
use them for. So, for example, the enzyme that breaks down grease in
biological washing powders can be modified to make it more stable at
higher temperatures, so it will still work in a hot wash. This process
of 'improvement' is called protein engineering.


2. Applications in medicine.


2.1. The first applications of this new technology were for
human medicine, and that involved the isolation, characterisation and
utilisation of human genes. That was not easy; there are 70-100,000
genes in the human cell, and the process is literally like finding the
needle in the haystack. However, the process of isolation of a human
gene, introducing it into a bacteria and getting it to work there is
now straightforward. That is not to say that it is easy; what is
called 'gene cloning' in the trade is now much easier than it was, but
is still difficult. I led a team that isolated the genes for human
interferon in the early 80's and it was very, very hard, and we weren't
first anyway. I don't think I have ever worked so hard in such a
repetitive fashion in my life! But the difficulties have been solved,
and we can make now make human proteins such as insulin, growth hormone
or interferon in bacteria. These are high value/low volume products
and were initial targets not only because they were needed for human
medicine but also because they were the obvious first targets for
commercial development. So what is sometimes called 'red
biotechnology', as opposed to 'green biotechnology' was born, and the
implications for the pharmaceutical industry have been profound.


2.2. To state the obvious; the old species barriers have gone. Any
product from any source can now be made in any host, and although all
the first generation of products were made, for technical reasons, in
bacteria, now insect, yeast or animal cells can all be used - grown in
lots of tens of thousands of litres in huge fermenters for an ever
expanding market. But there is another implication; products that once
were rare can now be made in gram amounts. So there was a profound
effect on the interferon trials - whether against cancer or viruses -
which had always been limited by the amount available. In principle,
any of the hundreds of products made by the body - often in minute
amounts, so, for example, the group of substances called the
lymphokines, which act like hormones for the immune system, can now be
cloned and produced in large amounts.


2.3. The products, after some initial hesitation - over insulin in
particular, have been totally accepted; and the only problem for the
consumer, or more precisely, the patient, is the price and you may be
familiar with the problems in the UK over the costs, and hence the
rationing, of
interferon-
SymbolbTimes_New_Roman
for treatment of MS.


2.4. What about the risks of these processes? Risk assessment involves
identifying all the possible hazards and then ascribing a probability
to each one of them. Both the nature of the hazard and its probability
can be difficult to determine, and this is certainly true for new
products, especially those from genetic modification, where the
technology is so new and the risks unknown. And the hazards? The
first question is whether the product is safe, and here highly
developed drug safety procedures swing into action. There have been no
problems with the drugs, although there was a problem with the food
additive tryptophan, an amino acid which is taken in gram amounts by
some. Such products are assessed by the drug safety procedure in the
UK, but not in the US, and there, a serious illness developed in
several hundred users, due, it was claimed by the green lobby groups,
to the fact that the product was made by genetic engineering. It is
almost certain that the damage is due to a minor contaminant in the
product, which was there because the tryptophan purification process
had been changed. But it is must have been a very expensive mistake.


2.5. But what about possible health risks for the scientists and
technical people involved in the production of these new products? And
what about the risks to the environment? There are very tough rules in
place, which are the responsibility of the Health and Safety Executive
in the UK. Experiments are categorised as to potential risk and this
risk then determines the level of isolation of the laboratory worker,
the production plant and the way in which the waste products are
disposed of. I know of no problem in the UK, and I was a member of the
relevant regulatory committee for nine years.


3. The development of genetically modified plants.


3.1. We can also modify both plants, and animals, in exactly the
same way, and it is now possible to transform any crop plant
efficiently with single genes, and techniques for transformation with
gene clusters are coming. This new technology will lead to many new
crop products, of several general types:

Symbol
Times_New_RomanModifications of
the genetic material of plants to switch off a particular gene or
genes. This has been used to extend the shelf life of tomatoes, by
switching off the gene that causes breakdown of the plant cell wall,

Symbol
Times_New_RomanIntroduction of
new genes, or enhancement of the activity of existing genes, to improve
starch or oil yield, or to produce modified oils or starches, to
enhance fruit flavour, colour or nutrition,

Symbol
Times_New_RomanModification of
the genetic material of plants to produce novel parental lines for the
production of new hybrids, for example rape, with enhance yields,

Symbol
Times_New_RomanModification of
the genetic material of plants to introduce resistance to herbicides or
pests, for example, soya, potatoes, cotton and corn,



and, in the longer term:



Symbol
Times_New_RomanIntroduction of
whole new genetic systems into the plant to increase, say, yields from
photosynthesis or to enable crops such as wheat to fix nitrogen. This
is proving to be very difficult.


3.2. It is very difficult to predict exactly when these new
developments will become available, but it is possible to arrange them
in an approximate time sequence:

Symbol
Times_New_RomanContinued
development of rapid genetic typing methods to speed conventional plant
breeding,

Symbol
Times_New_RomanContinued
development of plants resistant to herbicides and a wide variety of
pathogens,

Symbol
Times_New_RomanContinued
development of novel fertility systems for F1 hybrids with increased
yields,

Symbol
Times_New_RomanContinued
development of fruits and vegetables with longer shelf-lives,

Symbol
Times_New_RomanModification of
crops to produce oils with properties more suitable for industrial use,
fats more suitable for the human diet and starches for either dietary
or industrial use,

Symbol
Times_New_RomanIsolation of
genes that control flower shape and colour for the horticultural
industry,

Symbol
Times_New_RomanModification of
fruits and vegetables to improve flavour and nutritional content,

Symbol
Times_New_RomanElimination of
genes for toxic or allergic substances,

Symbol
Times_New_RomanIsolation and
utilisation of the complex systems that control salt tolerance and
drought resistance,

Symbol
Times_New_RomanIsolation and
modification of genes that control plant development and
differentiation, for example, the genes responsible for short-stalked
wheat or the genes responsible for control of the response to day
length. In this way, crops such as rape could be grown further north in
Canada or Sweden,

Symbol
Times_New_RomanModification of
trees for pest and disease resistance,

Symbol
Times_New_RomanProduction of
drugs and vaccines in plants,

Symbol
Times_New_RomanIntroduction of
new genetic systems to increase plant yield, for example, modifying
photosynthesis or enabling crops such as wheat to fix nitrogen,

Symbol
Times_New_RomanApplications to
crops such as cassava, important for the developing world.


3.3. To take a specific example, genetic modification of potatoes
could:

Symbol
Times_New_RomanIncrease the
availability of UK varieties by extending the growing season,

Symbol
Times_New_RomanImprove flavour
and mash texture through modification of starch and sugar content,

Symbol
Times_New_RomanReduce the water
content and alter cell-wall composition to limit the fat retained in
crisps and chips,

Symbol
Times_New_RomanExtend
shelf-life by suppressing sprouting and reducing rot,

Symbol
Times_New_RomanReduce chemical
residues by introducing herbicide tolerance, disease- and
pest-resistance traits.


3.4. An indication of the spread of transgenic crops can be gained from
some recently published figures. The global area (excluding China) of
transgenic crops was 1.7 million hectares in 1996, 11.0 million
hectares in 1997 and 27.8 million hectares in 1998, a 15 fold increase
in three years. These are very high adoption rates for new
technologies by agricultural standards. The five principal transgenic
crops grown in 1998 were, in descending order of area, soya, maize,
cotton, rape, and potato; with soya and cotton accounting for 52% and
30% of the global area. The principal benefits reported include more
flexibility in crop management, decreased dependency on conventional
insecticides and herbicides, higher yields and cleaner and higher grade
of end product. In the US in 1997, the economic benefit to growers was
estimated at $81 million for Bt cotton, $119 million for Bt corn and
$109 million for soya, with a collective total of $315 million, up from
$92 million in 1996.


3.5. So what else is driving the genetic modification of plants?
Primarily, many say, the need to feed a growing world population.
Global population is increasing by 87 million per year, and is
estimated to reach 8 billion by 2020 from its present 5.9 billion. In
addition, loss of land to urbanisation means that the amount of
cultivated land supporting food production has fallen from 0.44 ha per
person in 1961 to 0.26 ha per person now, and is projected to fall to
0.15 ha per person by 2050. The need for irrigation is increasing, the
climate is changing and as people become more prosperous, they replace
plant foods with animal foods-which are less efficient in trapping
solar energy. So about one-half of the grain produced in Europe, North
America and Russia is already used as feed. How are we going to feed
all these people? Surely new approaches will be needed in addition to
the continued improvement of existing methods ?


3.6. On the other hand, others say that genetic modification is not
needed to produce more food. They argue that the planet's food
problems are due to economic and political problems, not because we
can't grow enough, and that poverty in particular, makes it impossible
for people to buy food even when it is available. There's truth in
that; for if the world's food supply in 1994 had been evenly
distributed, it would have provided an adequate diet of about 2350
calories per day for 6.4 billion people, more than the world
population. But distributing it evenly will not be easy, even if the
world's population was not increasing. There are many other problems
in the future which will not be solved by redistribution; for example,
by 2020 half the worlds population will not have enough water available
to grow their own food, and they will have to depend on food imports.
My own view is that of course we should try to change some of the
practices that limit food supply, and of course biotechnology is only
part of the answer, but it seems perverse, even immoral, to me to walk
away from a potential increase in the world's food supply. I believe
that it is not only possible, but essential, to introduce genetically
modified crops for the developing world although we shall need care,
and political will, to avoid undue disruption of social systems.
Previous new technologies, for example universal vaccination, have been
controversial in their time, but where would we be without them?


3.7. Let me briefly mention three examples of ways in which
biotechnology could help the developing world. First, the introduction
of rice modified by increased levels of beta-carotene would help deal
with the problems due to the lack of vitamin A. In developing
countries and in Asia particularly, one hundred and eighty million
children suffer from Vitamin A deficiency and each year two million die
from diseases linked to Vitamin A deficiency. This is a particularly
serious problem for many poor children in Asia who are weaned on rice
gruel and little else. Similar introduction of rice with an over
threefold increase in available iron would help deal with the chronic
problem of anaemia in women in SE Asia. Third, scientists in Mexico
have added genes to rice and maize that help plants tolerate high
concentrations of aluminium, a soil toxicity problem that constrains
cereal production over vast areas of the tropics. Finally, the recent
isolation of the gene that is responsible for the dwarfing of wheat, a
change that we are all familiar with, has the advantage of
concentrating energy on grain production rather than on straw biomass.
The isolation of this gene, which turns out to be very similar in many
plants, means that this gene, which was so important in the massive
increase in yield in the 'green revolution' can now be transferred to
other crops such as basmati rice (Peng et al., Nature, Vol. 400, p.256,
15 July 1999). Here is a situation where genetic modification offers a
clear advantage over plant breeding; for in plant breeding two
different sets of 25.000 genes are brought together and the product is
selected for a particular new property. In doing so, many of the
qualities which make a particular variety particularly suitable for a
particular ecosystem are lost. In contrast, with GM, the gene to
produce dwarfing is introduced into that variety which is most suitable
for the environment. GM, despite the greatly exaggerated claims of the
Green groups, can bring clear environmental advantages. It is highly
significant that seven academies of science (not companies note!) from
developed and developing countries - Brazil, China, India, Mexico, the
UK, the US, and the Third World Academy of Sciences have recently
agreed to develop "an authoritative joint statement" on genetic
modification in world agriculture, making clear that it expects to
agree that the technology is needed to feed future populations, and
that we need to think through - now - the implications.


3.8. It is possible to modify animals in much the same way; and
specifically by injecting the cloned gene into the fertilised egg of a
sheep or a goat - the animals that have been worked with most so far.
The immediate objective here is to use such 'transgenic' animals to
produce the same sort of high value/low volume products that I
described earlier - pharmaceuticals. By attaching a tissue-specific
promoter to the gene, it is possible to arrange for the product to be
made only in a certain tissue, say the mammary gland, and then the
product is secreted into the milk. In this way the animals can produce
large amounts of the product, and in a form which is exactly the same
as is found in the human; specifically having the right sugar molecules
attached, and that doesn't always happen with bacteria. These systems
are just coming through into commercial development. It is also
possible, in theory, to modify animals so that they produce less fat
for example, and although this is little more than an extension of
traditional breeding techniques, it is likely to meet such consumer
resistance that such developments are, in my view, years away.


4. Uses of genetic modification in the food industry.


4.1. Genetically modified foods have entered British
supermarkets over this last year. The outcome has been mixed; for some
were accepted without hesitation-for example, the puree made from
genetically modified tomatoes. But the flour from genetically modified
soya beans has caused a huge amount of controversy, and food
manufacturers have now ceased to use this product in the UK, although
not in the US. Why is this? If it's OK to use genetic modification
for medicine then why not for food? Is GM soya unsafe, and will these
crops damage the environment? What are the risks?


4.2. The first two products-the tomato paste and 'vegetarian cheese'
offered the consumer both advantage and choice. For example, both
Safeway and Sainsbury sold 170 g of the modified tomato paste at the
same price as 142g of the conventional product-because there is so much
less loss in transporting the tomatoes from the field to the processing
plant, and furthermore, it tastes better. Not surprisingly, the GM
puree outsells the conventional product-for they are offered side by
side on the shelf.


4.3. In contrast, the flour from the herbicide-resistant soya, from
Monsanto in the US, offers no obvious advantage to the consumer, but
rather to the producer, and the consumer has not been
offered choice. Of course, the increased yields from this crop should
stabilise or possibly even lower the price of the product, and some
recent figures I have seen for maize suggest that roughly 25% of the
increased value goes to the company, 50% to the farmer and 25% to the
consumer. I don't have the figures for soya, but the consumer cost
advantage will be very hard to see when soya makes up such a small
amount of many products. So although all the evidence - including the
fact that 300 million Americans have been eating it for several years
without mishap - is that GM soya is as safe as normal soya, it offers
the consumer no advantage, and the scare stories might just be true.
So avoiding it is a perfectly understandable reaction, but this is
interpreted by the Green groups as evidence that a large majority of
the British public are against GM as such. I doubt whether that is
true.


4.4. So, is this new soya safe? Herbicide resistant soya was
genetically modified by the introduction of a gene from a soil
bacterium to make the plant resistant to the herbicide glyphosate.
Before it can be sold in Britain, it needs Government approval and
Ministers take the advice of the Advisory Committee on Novel Foods and
Processes, which I chaired for nine years. Now we do not eat soya
beans but the flour made by grinding and defatting the beans. Both the
added gene and the new enzyme are degraded by this treatment, and they
then will be quickly broken down in the gut. The Committee, which
includes a consumer representative and an ethical advisor, considered
this new soya to be as safe as conventional soya, and so advised the
Minister.


4.5. But trust in the regulatory process has been eroded, especially by
the BSE outbreak, and this Government is working hard to re-establish
trust in the regulatory system by opening up the approval procedure.
Agenda and summaries of decisions by the Novel Foods Committee have
been published for years, and now Minutes are being published, the
Internet is being used for rapid, widespread communication, and
consideration is being given to increasing the number of consumer
representatives, and meeting in public. Such changes will be essential
to restore public confidence, but may not be sufficient, and in my
judgement, the approval process will have to continue to be opened up.


4.6. What about the effect on the environment? The public have been
very concerned about the possibility of such effects. Will these crops
lead to an increase in the use of herbicides? Will the modified genes
escape into the environment to fill our fields with resistant rape, or
will the genes spread to other species? A number of environmental
groups have been very concerned about risks in this area, and political
pressures have focused on a call for a 'moratorium' on the planting of
all genetically modified crops in Britain, even though such a
moratorium would be illegal under EU rules. For example, English
Nature is concerned about the environmental effects of such plantings
and want a period of three to five years to plan and carry out
appropriate research. They point out that the English countryside,
especially, is very different from that in North America where farm
land and natural land-for example in their splendid National Parks-are
far apart, whereas in England especially they are cheek by jowl. The
Soil Association is chiefly concerned with the promotion of organic
farming, and so wants to prevent contamination of organic produce by
pollen from GM crops, which they regard as unnatural; so they want
either a ban or possibly a total separation of land used for organic
farming from that used for GM crops. Greenpeace want a long term ban
of all genetically modified crops.


4.7. These pressures have led Government to announce an agreement with
the plant breeders to delay the introduction of commercial planting of
such crops, and in the meantime, to conduct a series of farm scale
evaluations of the risks associated with the growth of GM crops in the
UK. These are now under way; although it is deplorable that Greenpeace
have taken the law into their own hands and have destroyed several of
these trials. I do not believe that we can resolve issues in an
advanced democracy like ours in this way. My judgement is that GM
crops are no more likely to spread their pollen than the crops that we
have been growing for years, and certified seed is already grown under
conditions that produce 99.9% pure seed. But if organic farmers want
to ensure that the rape that they grow has absolutely no
'contamination' at all from GM rape, and if by 'no' they mean zero,
then we have a very difficult problem to solve.


5. So why are consumers so concerned?


5.1. If GM soya is as safe as unmodified soya, and we can
control adverse effects on the environment, do consumers want to eat
it? Certainly, some do not. Why are consumers so concerned? There
have been a number of thoughtful articles on this topic; for example a
publication from the Dept. of Health, which points out that: "Risks are
generally more worrying if perceived:

Symbol
Times_New_Romanto be
involuntary (e.g. exposure to pollution) rather than voluntary (e.g.
smoking),

Symbol
Times_New_Romanas inequitably
distributed,

Symbol
Times_New_Romanas inescapable
by taking personal precautions,

Symbol
Times_New_Romanto arise from an
unfamiliar or novel source,

Symbol
Times_New_Romanto arise from
man-made rather than natural sources,

Symbol
Times_New_Romanto cause hidden
and irreversible damage,

Symbol
Times_New_Romanto pose some
particular danger to future generations,

Symbol
Times_New_Romanto threaten a
form of death or illness/injury arousing particular dread,

Symbol
Times_New_Romanto damage
identifiable rather than anonymous victims,

Symbol
Times_New_Romanto be poorly
understood by science,

Symbol
Times_New_Romanas subject to
contradictory statements from responsible sources,"


GM soya scores ten out of eleven from the Department of Health
fear-factors. No wonder there has been trouble!


5.2. We are getting very sensitive to talk of risk, particularly as
other threats to our safety recede. We live in a 'blame culture' where
somebody is responsible, and culpable, for everything that goes wrong.
Anthony Giddens, this year's Reith Lecturer, has made the distinction
between 'natural risks', such as earthquakes etc., and 'manufactured
risk', which is due to our activity. I think that it is more
complicated than this, and I would want to make a further distinction
between those risks we choose to take, and those that are thrust upon
us, and yet a further one between risks linked to medicine and those
linked to food. Risk issues are not simple. There is another
difficulty - science can only ever say that there is no evidence of
risk, while the public now asks for evidence of no risk. That can
never be supplied - with GM foods, mobile phones, or any other new
technology.


5.3. So for reasons such as these, consumers want to make their own
decisions, rather than trust the experts. And what are the reasons for
this loss of consumer confidence? Let me suggest several:

Symbol
Times_New_RomanFirst,
scientists, and the expert approval processes, are no longer trusted as
they once were. The BSE epidemic has of course been disastrous for
confidence.

Symbol
Times_New_RomanSecond, I think
the public is largely unaware of the development of careful scientific
methods of assessing risk, such as the use of hazard analysis, to come
much closer to an 'objective' evaluation of risk. But it is also true
that we find great difficulty in explaining, and the public in
understanding, what is meant by different degrees of risk. Our
National Lottery-with its slogan of "It could be you" does not help
either-the message is clear: even what is very unlikely may happen. So
even if the risk from a new product is very low, maybe it will be me!

Symbol
Times_New_RomanThird, the
public finds it difficult to know how seriously to take the points put
by the many single-issue pressure groups.

Symbol
Times_New_RomanFourth, risks
are assessed differently according to the context. We will accept
quite high risks when we are seriously ill, but will not tolerate much
risk at all with food.


5.4. One explanation for such conflicting views is that scientists and
the public work from different value systems. Scientists and
technologists see novel applications of new discoveries as logical and
reasonable-and characterise all opposition as unreasonable. "If only
they understood what we are doing" they say "the public would agree
with us." Experience tells that this is not always true. Scientists
and technologists are used to an uncertain world, where knowledge is
always flawed, can handle risk judgements more easily, and are
impatient of those who differ from them. The public's reaction is
quite different, and it can be described as:

Symbol
Times_New_RomanOutrage - "how
dare they do this to us?" - the way the public now regards Monsanto.

Symbol
Times_New_RomanDread - the way
we would regard a nuclear power station explosion.

Symbol
Times_New_RomanStigma - the way
the public regard food irradiation.


5.5. The net effect of this is that it is not possible to predict the
way in which the public will react to a new risk by consulting just
scientists and technologists, and perception of risk is now much more
important than any technical assessment of risk in the introduction of
new technology.


5.6. So all these issues are raised by GM foods, but are they intrinsic
to the technology? Rather, I believe that GM foods have become a
lightning rod for many modern concerns; scepticism about the regulatory
process, gusts of anxiety about our food, growing hostility to high
intensity agriculture, and concern about the way in which the agrifood
business has consolidated into about six companies world-wide. So
decisions about the future of our food are being taken in the US or in
Switzerland. Consumers feel they have lost control and blame the
technology, and some wish to ban it altogether. I do not believe that
that is a sensible way ahead. I believe that should respond by
regulating this coming change, which I believe is already with us, so
that it is the least harmful and the most helpful to us all.


6. But what about the future?

6.1. My view is that genetic modification of crops for food use
is here to stay, certainly in North and parts of South America and
Asia, and inevitably in Europe. Although the future is now less
certain because of Monsanto's clumsy introduction of modified soya, it
is worth stressing that herbicide resistant and insect resistant crops
are first generation products. Second generation crops which will
tackle more sophisticated problems are in development-herbicide
resistance is early 80's technology. These new targets must have
consumer benefits - and taste and nutritional value are high priorities
here. We must also deliver benefits for the farmer and for the
developing world. At the political and regulatory level, we must
ensure that the consumer is able to exert choice, knows what is in the
product, and crucially, has regained confidence in the regulatory
process.
Professor Burke was Chairman of the Advisory Committee on Novel
Foods and Processes from 1989-1997, and Vice-Chancellor of the
University of East Anglia from 1987-1995.