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Taking Science Seriously in the GM Debate
Contribution to Committee on Agricultural Biotechnology, Health, and
the Environment Workshop, The National Academies, Washington DC, 16 April
2001.
Mae-Wan Ho, Institute of Science in Society, 24 Old
Gloucester St., London WC1N, 3AL, UK
Science in crisis
If there is one thing that distinguishes the Third World from the
industrialised countries, it is that they take science a lot more
seriously than we do in the GM debate.
I was researcher and university lecturer of genetics throughout the
mid-1970s to the early1980s when new discoveries on the fluid genome made
headlines every week. Researchers back then were building a new paradigm,
dispelling once and for all the notion that a gene is constant and
independent of context. The thought that a gene could be patented as an
invention probably never crossed their mind. And if it did, they would
have dismissed it as a joke. Craig Venter of Celera may have only just
discovered that genetic determinism cannot deliver the goods after he's
sequenced the human genome. But many of us knew that genetic determinism
had died with the revelations of the fluid genome, if not before [1]. And
now, almost two decades later, science is in crisis in more ways than one.
The paradigm change that should have occurred, did not. On the contrary,
the scientific establishment remained strongly wedded to genetic
determinism, which has misguided genetic engineering, making even the most
unethical applications appear compelling, such as therapeutic
human cloning, for one [2]. Bioethics became a contradiction in terms as
rampant commercialisation of science took hold.
Since the 1980s, preoccupation with patenting and start-up companies has
compromised the quality of molecular genetics research, stifling basic
science and innovation, and failing to serve the public good. Worse still,
many scientists are consciously or unconsciously ignoring scientific
evidence of the hazards. I got involved in the genetic engineering debate
in 1994, to try to inform our policymakers and the public, and to start
debate and discussion from within the scientific community.
For the past seven years, I have had to follow developments in genetic
engineering science much more carefully and extensively than many of the
practitioners, only to find that all my fears concerning the problems and
dangers of genetic engineering are being confirmed. I shall highlight some
of these before going to discuss what needs to be done.
Genetic engineering superviruses
The top news in the Jan. 13 issue of the New Scientist [3] was
on a deadly virus created accidentally by researchers in Canberra
Australia, who were trying to genetic engineer a contraceptive vaccine for
mice [4]. They spliced a gene for the protein interleukin-4 (IL-4) into a
relatively harmless mousepox virus in the hope that IL-4 would boost the
immune system. When they injected the recombinant virus into mice
belonging to a strain genetically resistant to mouse-pox virus, all the
mice died. IL-4 suppressed both natural killer cells and cytotoxic
lymphocytes responses to viral infection. The recombinant virus also
killed 50% of the genetically resistant mice that were immunized against
mouse-pox virus.
That is not all. The IL-4 gene, spliced into the vaccinia virus, was
found to delay clearance of the virus from experimental animals, and to
undermine the animals anti-viral defence [5,6]. Vaccinia and
mouse-pox both belong to the family that contains the human smallpox
virus, raising the spectre of biological warfare. But the far greater
danger lies in the unintentional creation of deadly pathogens in the
course of apparently innocent genetic engineering experiments. Some
scientists are already creating viruses deliberately in their
laboratories, just to show it could be done, or in the course of cloning
existing viruses [7]. And dangerous recombinant viruses and bacteria may
also be inadvertently created in making vaccines against AIDS, as Yugoslav
virologist Veljkovic has been warning since 1990 [8].
The New Scientist editorial [9] accompanying the report remarked
that five years ago, when biomedical researchers were asked if genetic
engineering could create "a virus or bacteria more virulent than
natures worst", they replied it would be "difficult if not
impossible".
Some of us have been warning of accidents such as this for
at least the past six years. The basic tools of genetic engineering are
bacteria, viruses and other genetic parasites that cause diseases and
spread drug and antibiotic resistance. All that fall into the hands of
genetic engineers are exploited. Genes from dangerous agents, including
antibiotic resistance genes, are profusely mixed and matched, or
recombined. As every geneticist should know, recombination of genetic
material is one of the main routes to creating new strains of bacteria and
viruses, some of which may be pathogens. (The other route is mutation.)
Moreover, the predominant orientation of genetic engineering in the past
two decades has been to design artificial GM constructs and vectors that
cross species barriers and invade genomes, both of which will enhance
horizontal gene transfer and further increase the chance for
recombination.
We published a detailed review on the possible links between genetic
engineering and the recent resurgence of drug and antibiotic resistant
infectious diseases in 1998 [10]. We were by no means the first. Those who
pioneered genetic engineering declared a moratorium in Asilomar in the
mid- 1970s precisely because they were concerned about this dire
possibility. Unfortunately, overwhelming pressures for commercial
exploitation cut the moratorium short. The scientists set up guidelines,
based largely on assumptions that have all fallen by the wayside as the
result of new scientific findings. The two most important findings are the
persistence of nucleic acids in all environments including the gut of
animals, and the ease with which nucleic acids can get into all cells,
especially those of human beings, as shown in so-called gene therapy
research [11].
Instead of tightening the guidelines, our regulators have relaxed them.
Transgenic wastes are being recycled as food, feed, fertilizer and
landfills under the current EC Directive on Contained Use [12], and I
would not be surprised if this applies also in the US. There is a lesson
to be learned from the 650 or more adverse reactions associated with gene
therapy trials, including several deaths. The same kinds of constructs are
made, whether it is to genetic engineer human beings or plants and
animals, and the same crude first generation technology is used.
The instability of transgenic lines
The instability of transgenic lines has been well known since 1994,
particularly in connection with gene silencing. This not only affects
agronomic performance, but also safety. We have drawn attention to the
structural instability of GM constructs in general, which may
enhance horizontal gene transfer and recombination, especially because the
cauliflower mosaic virus (CaMV) 35S promoter, present in practically all
GM crops already commercialized or undergoing field trials, actually has a
recombination hotspot. We raised our concerns in a series of scientific
papers [13 -16].
In the course of debating with plant molecular geneticists in UK's top
research institute, the John Innes Centre (JIC), we discovered that the
CaMV 35S promoter is active, not only in all plants, bacteria, algae and
yeast, but also in animal and human cells [17,18]. None of our critics was
aware that the promoter is active in human cells, including a molecular
geneticist on the UK Agriculture & Environmental Biotechnology
Commission set up to oversee our farmscale field trials [19].
This year, researchers in JIC admitted in their annual report that GM
crops are unstable and prone to recombination. But when we pointed this
out [20], they issued a strong denial, and accused us of ignoring one of
their papers where they claim to have demonstrated that transgenic rice
lines are stable. I have since reviewed that paper in detail [21] and
concluded, "A generous interpretation of the data presented would
suggest that 7 out of 40 (18%) transgenic rice lines may be stable to the
R3 generation." In other words, at least 82% of the lines are
unstable. That paper is not at all exceptional in making claims in the
abstract, and often in the title, which are not supported by the evidence
presented [22]. No reply has yet come from the JIC since. My colleague,
Prof. Joe Cummins has summarised more up-to-date literature showing that
all GM crops may be unstable [23].
Roundup Ready soya has consistently performed less well than non GM soya
over the years, and this year's seeds are experiencing problems in
germination, according to a report from the University of Missouri [24].
Terminator crops at large
Last December, I was asked to act as expert witness in defence of
citizens who have taken civil action against GM crops which they strongly
believe to be a threat to health and biodiversity. Among the crops were GM
oilseed rape varieties used to produce F1 hybrids belonging to AgrEvo UK
(now Aventis). At the time, I was also preparing a joint submission, with
two other scientists, to the consultation document, "Guidance on Best
Practice in the Design of GM Crops" put out by the UK Governments
Advisory Committee for Release to the Environment (ACRE). One of the main
enabling technologies for best practice suggested
in the document is precisely Agrevo's seed/pollen sterility system, for it
prevents GM gene flow.
It soon dawned on us that the GM oilseed rape lines undergoing field
trials in the UK are engineered with terminator technology -
so named by critics because it renders harvested seeds sterile - for no
other reason than to enforce corporate patents on GM seeds. Not only that,
according to AgrEvos application, similar crops produced by the
company Plant Genetic Systems (PGS), a subsidiary of AgrEvo, have been
undergoing field-trials in Europe since the beginning of 1990.
In the US, similar male sterile lines engineered with the terminator-gene,
barnase have been tested at least as early as 1992. There have been 115
field trials, the vast majority done without risk assessment, as the first
environmental assessment came up with FONSI - Finding of No
Significant Impact. Crops modified for male sterility include rapeseed,
corn, tobacco, cotton. Brassica oleracea, potato, poplar, chicory, petunia
and lettuce. The USDA commercial release data include 4 crops with
barnase: a corn and a canola by AgrEvo, a chicory by Bejo, and another
corn by Plant Genetic Systems.
Separately, the other genetic component in terminator crops,
site-specific recombinase, has also been engineered into corn and papaya,
and there have been 14 field trials between 1994 and 1998, with no
environmental impact assessment at all.
There are more than 150 US patents listing barnase or site-specific
recombination or both, the oldest, on site-specific recombinase, going
back to 1987.
The first terminator patents that came to public attention were those
jointly owned by US Department of Agriculture and Delta and Pine Land
Company, which Monsanto had intended to acquire. The novelty in those
patents is the proposal to combine the terminator-gene system with the
site-specific recombinase system, giving the company complete control over
the hybrids as well as proprietary chemicals that control gene expression.
As a result of universal condemnation and rejection, Monsanto had
announced it will not commercialise terminator crops, to everyones
relief. Research and development, however, have continued unabated.
Everyone has assumed such crops only exist in theory, when they have been
out there for more than 10 years.
It is no coincidence that simultaneous consultation went on in the
United States on the USDA-Delta and Pine terminator patents. The USDA has
since committed itself to commercial development of the technology, and,
like the UK ACRE, also argued in its favour because it could prevent GM
gene flow. But it cannot [24], because male sterile lines will be
pollinated by non GM crops, and there is no way to prevent horizontal gene
transfer.
On the contrary, the increased complication of the constructs may
enhance horizontal gene transfer and recombination. The genes and gene
products themselves are also known to be harmful. The terminator-gene
barnase kills cells by breaking down RNA, an intermediate in the
expression of all genes. The recombinase, in theory, breaks and rejoins
DNA at specific sites, but is far from accurate and can scramble genomes.
A male transgenic mouse engineered with only one copy of Cre recombinase
was 100% sterile, because the recombinase enzyme managed to scramble the
genomes of both daughter spermatids when they are still connected by a
cytoplasmic bridge [25]. The mouse genome does not even have the lox
sites recognised by the Cre recombinase.
Terminator insects give wings to genome invaders
The US Department of Agriculture has approved field release of GM pink
bollworms this summer, made with a mobile genetic element, piggyBac,
already known to jump many species. The element was first discovered in
cell cultures of the cabbage looper, where it caused high mutations of the
baculovirus infecting the cells, by jumping into the viral genome. In
experiments in silkworms, researchers already found evidence that the
inserts were unstable, and had a tendency to move again from one
generation to the next [26].
"These artificial transposons are already aggressive genome
invaders, and putting them into insects is to give them wings, as well as
sharp mouthparts for efficient delivery to all plants and animals... The
predictable result is rampant horizontal gene transfer and recombination
across species barriers. The unpredictable unknown is what kinds of new
deadly viruses might be generated, and how many new cases of insertion
mutagenesis and carcinogenesis they may bring
" [27].
"Food biotech is dead"
I have presented only a small fraction of the scientific findings
indicating problems and dangers specific to genetic engineering, which
both the practitioners and regulators are ignoring or dismissing. These
and other concerns have persuaded more than 410 scientists from 55
countries around the world to sign an Open Letter to all Governments
demanding a moratorium on environmental releases of GMOs because they are
unsafe, and a ban on patenting life-forms and living processes because
those patents are unethical. They also demand support for non-corporate,
sustainable, organic agricultural methods that can truly bring food
security and health for all (www.i-sis.org.uk).
Since we launched the Open Letter two years ago, the terms of the GM
debate have shifted. It is no longer a moratorium that is needed. GMOs, as
currently made, are unsafe and unsustainable, as well as immoral. We must
abandon GM crops and all other attempts to genetic engineer plants,
animals and human beings with a technology that is widely acknowledged to
be unreliable, uncontrollable and unpredictable.
Even the corporations are coming around to the view that "Food
biotech is dead" [28]. One by one, Aventis, Monsanto and Syngenta
have announced they will concentrate on genomics and marker assisted
conventional breeding. Though meanwhile, they are still forcing the world,
especially the Third World to accept GM crops.
But the whole world is in revolt. The governments of Thailand and Sri
Lanka, among others, have banned GM crops and GM imports. In Indonesia,
armed guards had to be sent to protect Monsanto's shipment of cotton
seeds, which have already been shown not to perform as well as the
indigenous non GM variety [29]. In the Philippines, mass demonstrations
are taking place against GMOs and the International Rice Research
Institute (IRRI) by MASIPAG (Farmer Scientist Partnership for Development)
and other ngos. They condemn IRRI for restructuring sound traditional
practices over the past 40 years to make farmers dependent on chemical
inputs produced by corporations, the same corporations that are now
forcing GMOs on farmers with the help of IRRI [30]. People are demanding
farmer's rights over the genetic resources in the collection and genebanks
of IRRI and they renounce any form of IPR. Those sentiments are widely
shared, not just all over the Third World, but in Europe and the United
States.
The organic revolution
Europe is fed up with the intensive corporate agriculture that has
brought BSE and the food and mouth epidemic now threatening to get out of
control, and is going organic in earnest. The annual growth rate in
organic agriculture in Europe from 1989 to 1999 averaged 25%, which,
extrapolated forward, would lead to 10% of Western European agriculture
being organic by 2005, and 30% by 2010 [31]. The same is happening in the
rest of the world. As scientists, we must take all evidence seriously.
Organic and sustainable agricultural practices and technologies are
succeeding, documented in study after study, despite the appalling lack of
research funding compared to the hundreds millions that have gone into
biotech. At least 3% of the arable land, some 28.9m hectares in Africa,
Asia and Latin America are already farmed sustainably, with impressive
gains in crop yield as well as social, economic and health benefits [32].
Organic farming is also working well in the United States and Europe, with
yields matching and even surpassing agrochemical agriculture. Organic
farms are good for wild-life, supporting many more species of plants,
songbirds butterflies spiders, earthworms [33]. We need organic farming
for the world to feed itself and for the planet to regenerate and thrive.
Sustainable agriculture is also important for alleviating, if not
reversing global warming. A new report shows that sustainable agriculture
can contribute significantly, not only to reducing consumption of fossil
fuel, but increasing sequestration of carbon in the soil [34].
Sustainable agriculture is predicated on a holistic, ecological
perspective anathema to reductionist mechanistic science. Mechanistic
science has been thoroughly discredited in the course of the 20th century.
Mechanical physics went first of all with relativity and quantum physics.
Biology was the last to go with the new genetics.
The new genetics is radically ecological, organic and holistic. That is
why genetic engineering, at least in its current form, can never succeed.
It is based on misconceptions that organisms are machines, and on a denial
of the complexity and flexibility of the organic whole.
The challenge for western scientists is to develop a holistic science to
help revitalise all kinds of non-corporate sustainable agriculture and
holistic medicine that can truly bring food security and health to the
world.
References
- See Ho, M.W. (1998, 1999). Genetic
Engineering Dream or Nightmare? Turning the Tide on the Brave New
World of Bad Science and Big Business, Gateway, Gill and Macmillan,
Dublin, Continuum Books, New York.
- See "The unnecessary evil of
'therapeutic' human cloning" Mae-Wan Ho and Joe Cummins.
ISIS News 7/8 Feb. 2001
- Nowak R. Disaster in the making. New Scientist 2001: 13 Jan.
4-5.
- Jackson RJ, Ramsay AJ, Christensen CD, Beaton S, Diana F. Hall DF and
Ramshaw IA.Expression of Mouse Interleukin-4 by a Recombinant Ectromelia
Virus Suppresses Cytolytic Lymphocyte Responses and Overcomes Genetic
Resistance to Mousepox. Journal of Virology: 2001: 75:
1205-1210.
- Bembridge GP, Lopez JA, Cook R, Melero JA and Taylor G. Recombinant
Vaccinia virus coexpressing the F protein of respiratory syncytil virus
(RSV) and interleukin-4 (IL-4) does not inhibit the development of
RSV-specific memory cytotoxic T lymphocytes, whereas priming is dimished
in the presence of high levels of IL-2 or gamma interferon. Journal
of Virology: 1998: 72: 4080-7.
- van den Broek M, Bachmann MF, Kohler G, Barner M, Escher R,
Zinkernagel R and Kopf M. IL-4 and IL-10 antagonize IL-12-mediated
protection against acute vaccinia virus infection with a limited role of
IFN-g and nitric oxide synthetase 2. The Journal of Immunology:
2000: 164: 371-8.
- Reviewed in "Genetic engineering
superviruses" Mae-Wan Ho. ISIS Report, March 2001
- Prljic J, Veljkovic N, Doliana R,
Colombatti A, Johnson E, Metlas R. and Veljkovic V. Identificaion of an
active Chi recombinational hot spot within the HIV-1 envelope gene:
consequences for development of AIDS vaccine. Vaccine 1999: 17:
1462-7; see also "Genetic engineering
superviruses II" Mae-Wan Ho. ISIS Report March 2001
- "The genie is out" New
Scientist editorial 2001: 13 Jan. 3.
- Ho MW, Traavik T, Olsvik R, Tappeser B, Howard V, von Weizsacker C
and McGavin G. Gene Technology and Gene Ecology of Infectious Diseases.
Microbial Ecology in Health and Disease 1998: 10: 33-59.
- "Dangerous GM wastes recycled as
food, feed and fertilizer" ISIS News 6, September
2000
- Ho MW, Ryan A, Cummins J and
Traavik T. Unregulated hazards: 'naked' and
'free' nucleic acids. ISIS and TWN Report, Jan 2000
- Ho MW, Ryan A, Cummins, J.
Cauliflower Mosaic Viral Promoter - A Recipe for Disaster? Microbial
Ecology in Health and Disease 1999, 11: 194-197.
- Ho, M.W., Ryan, A. and Cummins, J. (2000). Hazards of transgenic
plants with the cauliflower mosaic viral promoter. Microbial Ecology
in Health and Disease 12, 6-11.
- Cummins, J., Ho, M.W. and Ryan, A. (2000). Hazards of CaMV promoter.
Nature Biotechnology 18, 363.
- Ho, M.W., Ryan, A. and Cummins, J. (2000) CaMV 35S promoter
fragmentation hotspot confirmed, and it is active in animals. Microbial
Ecology in Health and Disease (in press).
- Ballas,N., Broido, S., Soreq, H., and Loyter, A. (1989). Efficient
functioning of plant promoters and poly(A) sites in Xenopus oocytes Nucl
Acids Res 1989: 17: 7891-903.
- Burke, C, Yu X.B., Marchitelli, L.., Davis, E.A., Ackerman, S.
(1990). Transcription factor IIA of wheat and human function similarly
with plant and animal viral promoters. Nucleic Acids Res 1990:
18: 3611-3620.
- "UK farmscale field trials - a
tragi-comedy of errors" by Angela Ryan ISIS Report,
March 2001
- "UK
top research centre admits GM failure" by Mae-Wan Ho, Angela
Ryan and Joe Cummins, ISIS Report, Jan. 2001
- Gahakwa D, Maqbool SB, Fu X,
Sudhakar D, Christou P and Kohli A. Transgenic rice as a system to study
the stability of transgene expression: multiple heterologous transgenes
show similar behaviour in diverse genetic backgrounds. Theor Appl
Genet 2000: 101: 388-99.
- For another example see "Swallowing
the tale of the swallow tail, No 'absence of toxicity' of bt pollen"
by Mae-Wan Ho. ISIS News 5 July 2000
- "GM
crops may all be unstable" by Joe Cummins, ISIS Report April
2001
- See Ho MW, Cummins J and Bartlett
J. Killing fields near you. Terminator
crops at large. ISIS News 7/8, Feb. 2001
- Schmidt, E.E., Taylor, D.S.,
Prigge, J.R., Barnett, S. and Capecchi, M.R. (2000). Illegitimate
Cre-dependent chromosome rearrangements in transgenic mouse spermatids.
PNAS 97, 13702-7.
- Toshiki T, Chantal T, Corinne R, Toshio K, et al. Germline
transformation of the silkworm Bombyx mori L. using a piggyBac
transposon-derived vedctor. Nature Biotechnology 2000, 18, 81-4.
- Reviewed in "Terminator insects
give wings to genome invaders" by Mae-Wan Ho and "Terminator
insects - the killing of females" by Mae-Wan Ho and Joe
Cummins. ISIS Reports March 2001
- See The New York Times,
January 25, 2001.
- "GM cotton fails in Indonesia"
ISIS News7/8 Feb. 2001
- "Asia's farmers say no to GM
rice" MASIPAG news & Views Press Release, 4 April, 2001.
- "Snouts in the trough" by John Vidal. The Guardian Jan 10,
2001; The Organic Food and farming Report 1999, The Soil
Association, Bristol, UK.
- "Against the grain: could we feed the world without causing
further environmental damage?" Jules Pretty, The Guardian,
Jan. 16, 2001.
- The Biodiversity Benefits of Organic Farming. The Soil
Association, Bristol, UK, May 2000.
- Agricultural Influences on Carbon Emissions and
Sequestration: A Review of Evidence and the Emerging Trading Options.
Jules Pretty and Andrew Ball, Centre for Environment and Society and
Department of Biological Sciences, University of Essex, March 2001.
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