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Can biotechnology help fight world hunger?
Dr. Mae-Wan Ho
Special Forum organized by Congressman Tony Hall,
Capitol Hill, Washington DC, 29 June 2000
Key Words: GM crops, CaMV promoter, horizontal gene transfer, world
hunger, organic revolution in science.
1. It’s a great honor to be invited to speak here. I’m a
scientist who loves science and believes science and technology can
help build a better world and combat world hunger. But it must be the
right kind of science and technology, and it must be decided by people
themselves. There is no alternative to the democratic process of seriously
informing and empowering people. And I congratulate Congressman Tony Hall
for putting on this special forum.
2. I am among the 327 scientists from 38 countries who have signed an
Open Letter to all Governments demanding a moratorium on GM crops because
we have reasons to believe they are not safe (1). We are also calling for
support of sustainable agricultural methods that are already working
successfully around the world.There is genuine disagreement within the
scientific community. The public are not served by portraying the debate
as science versus anti-science.
3. Let me begin with recent report from Germany that GM genes in GM
pollen have transferred to the bacteria and yeasts in the gut of baby bees
(2).
4. This kind of horizontal gene transfer involves the direct uptake of
foreign genetic material. It has been found to happen also in the field.
After GM sugar beet was harvested, the GM genetic material persisted in
the soil for at least two years and was taken up by soil bacteria (3).
5. Not only microorganisms, but animal cells, including human cells can
readily take up the GM constructs and the foreign genes often end up in
the cell’s own genetic material, its genome (4).
6. Not so long ago, the pro-biotech scientists were insisting horizontal
gene transfer couldn’t happen. Now, they are saying it happens all
the time, so no need to worry.
7. So the crucial question is whether GM genetic material is like
ordinary genetic material. The answer is no. There is a world of
difference between GM genetic material and natural genetic material
8. Natural genetic material in non-GM food is broken down to provide
energy and building-blocks for growth and repair. And in the rare event
that the foreign genetic material gets into a cell’s genome, other
mechanisms can still put the foreign genes out of action or eliminate it.
These are all part of the biological barrier that keeps species distinct,
so gene exchange across species is held in check. And that has been so for
billions of years of evolution.
9. GM-constructs are designed to invade genomes and to overcome natural
species barriers. Because of their highly mixed orgins, GM constructs tend
to be unstable as well as invasive, and may therefore be more likely to
spread by horizontal gene transfer (5).
10. GM constructs consist of genetic material of dangerous bacteria,
viruses and other genetic parasites from widely different origins. They
are combined in new ways that have never existed, and put into genomes
that they have never been part of. They include antibiotic resistance
genes that make bacterial infections very difficult to treat. And, you
never just put a gene in by itself. It needs a gene switch or a promoter
to work. Typically an aggressive promoter from a virus is used to make the
gene over-express continuously – something which never happens in
healthy organisms.
11. One viral promoter in practically all GM crops out there, including
the so-called second generation GM plants such as the ‘golden rice’
(6) is from the cauliflower mosaic virus, CaMV for short. This CaMV
promoter has a recombination hotspot – a site where it is prone to
break and join up with other genetic material (7). It is promiscuous in
function (8). Plant genetic engineers thought it works in all plants and
plant-like species, but not in animals. Just last week, we discovered in
the scientific literature more than 10 years old that this same CaMV
promoter works extremely well also in frog eggs (9) and extracts of human
cells (10). It is already known to be able to substitute for promoters of
other viruses to give infectious viruses.
12. What will happen when these dangerous GM constructs spread?
Remember, GM constructs are made from genetic material of viruses and
bacteria and are designed to cross species barriers and to invade genomes.
In the process, there’s the obvious potential that they may recombine
with viruses and bacteria to create new strains that cause diseases. The
antibiotic resistance genes may also spread to bacteria associated with
serious diseases such as meningitis and tuberculosis. GM constructs that
invade genomes may recombine with, and wake up dormant viruses that have
now been found in all genomes (reviewed in 8).
13. GM crops are turning out to be useless as well as unsafe. The
bacterial bt-toxins, engineered into many crops, are poisonous for
beneficial and endangered species such as lacewings, the Monarch butterfly
as well as the black swallowtail (11). Bt crops encourage new resistant
pests to evolve. Stink Bugs in North Carolina and Georgia are eating up
the bt-cotton crops (12) and have to sprayed with deadly pesticides. A
study in the University of Nebraska shows that GM Roundup Ready soya
yielded 6-11% less than non-GM soya (13), confirming an earlier Univ. of
Wisconsin study which also found that the GM soya required 2 to 5 times
more herbicides.
14. The way to fight world hunger is definitely not GM crops. World
population figures have been wildly exaggerated. The figure of 10 billion
has been bandied about. In fact, figures have had to be revised downwards
several times in the late 1990s. By mid-1998, the UN’s estimate was
that world population will peak at 7.7 billion in 2040, then go into long
term decline to 3.6 billion by 2150, less than two-third of today’s
number (14).
15. Population arguments are based on the ecological concept of carrying
capacity. Ecologists are increasingly finding that the more biodiverse the
ecosystem, the greater the carrying capacity (15), and hence the more
people and wild-life it can support. Biodiverse systems are also more
stable and resilient. The same principles have guided traditional
indigenous farming systems, and are now being re-applied in holistic
approaches that integrate indigenous and western scientific knowledge
(16). Some 12.5 million hectares around the world are already farmed in
this way. The yields have doubled and tripled and are still increasing, at
the same time reversing some of the worst environmental, social and health
impacts of the green revolution.
16. World market for GM crops has collapsed because people all over the
world are rejecting them and opting for organic sustainable agriculture
(17). An organic revolution is rising from the grass-roots and also
sweeping across the disciplines within western science. From quantum
physics to the ecology of complexity and the new genetics, the message is
the same: nature is dynamic, interconnected and interdependent (18).
Proponents of GM technology are stuck in the mechanistic era, it is that
above all that makes the technology both futile and dangerous. It is just
not innovative enough!
17. In conclusion, GM crops are not safe, not needed and fundamentally
unsound. Far from helping to fight world hunger, they are standing in the
way of the necessary global shift to sustainable organic agriculture that
can really provide food security and health around the world.
Notes and References
- Open Letter from World
Scientists to All Governments calling for a moratorium on GMOs -
from www.i-sis.org.uk
- Barnett, A. (2000). GM genes ‘jump species barrier’ The
Observer May 28, 2000.
- Gebhard, F. and Smalla, K. (1999). Monitoring field releases of
genetically modified sugar beets for persistence of transgenic plant DNA
and horizontal gene transfer. FEMS Microbiology Ecology 28,
261-272; see also Horizontal
gene transfer happens" ISIS News #5 on www.i-sis.org.uk
- Reviewed by Ho, M.W., Ryan, A., Cummins, J. and Traavik, T. (2000).
Unregulated Hazards: ‘Naked’
and ‘Free’ Nucleic Acids, ISIS and TWN Report, Jan.
2000, London and Penang. www.i-sis.org.uk
- See Old, R.W. and Primrose, S.B. (1994). Principles of Gene
Manipulation, 5th ed. Blackwell Science, Oxford; Kumpatla, S.P.,
Chandrasekharan, M.B., Iuer, L.M., Li, G. and Hall, T.c. (1998). Genome
intruder scanning and modulation systems and transgene silencing. Trends
in Plant Sciences 3, 96-104.
- This can be seen in the scientific report itself: Ye, X., Al-Babili,
S., Kloti, A., Zhang, J., Lucca, P., Beyer, P. and Potrykus, I. (2000).
Engineering the provitamin A (b-carotene) biosynthetic pathway into
(carotenoid-free) rice endosperm. Science 287, 303-305; see also
ISIS Sustainable Science Audit
#1: The Golden Rice – An Exercise in How Not to Do Science -
from www.i-sis.org.uk
- Kohli, A., Griffiths, S., Palacios, N., Twyman, R.M., Vain, P.,
Laurie, D.A. and Christou, P. (1999). Molecular characterization of
transforming plasmid rearrangements in transgenic rice reveals a
recombination hotspot in the CaMV 35S promoter and confirms the
predominance of microhomology mediated recombination. Plant J. 17,
591-601; Kumpatla, S.P. and Hall, T.C. (1999). Organizational complexity
of a rice transgenic locus susceptible to methylation-based silencing.
IUBMB Life 48, 459-467.
- Ho, M.W., Ryan, A. and Cummins, J. (1999). Cauliflower mosaic viral
promoter – a recipe for Disaster? Microbial Ecology in Health
and Disease 11, 194-197; Cummins, J., Ho, M.W. and Ryan, A. (2000).
Hazards of CaMV Promoter? Nature Biotechnology April; 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 (in press).
- N 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 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 18,
3611-20.
- Wraight, C.L., Zangerl, R.A., Carroll, M.J. and Berenbaum, M.R.
(2000). Absence of toxicity of Bacillus thuringiensis pollen to
black swallowtails under field conditions. PNAS Early Edition
www.pnas.org; see also
Swallowing the tale of
the swallowtail and To
Bt or Not to Bt, ISIS News #5 from www.i-sis.org.uk
- "Research Shows Roundup Ready Soybeans Yield Less". News
Release from IARN News Service, University of Nebraska
IANRNEWS@unlnotes01.unl.edu
- See Biodemocracy News #27 www.purefood.org
- World Population Projections to 2150, UN Population Division, New
York, 1998.
- See Tilman, D., Wedin, D. and Knops, J. (1996). Productivity and
sustainability influenced by biodiversity in grassland ecosystems.
Nature 379, 718-720.
- See Altieri, M., Rosset, P. and Trupp, L.A. (1998). The Potential
of Agroecology to Combat Hunger in the Developing World, Institute
for Food and Development Policy Report, Oakland, California; also
Rosset, P. personal communication.
- Over the past four years, US corn exports to the EU have fallen from
$360 million a year to near zero, while soya exports have fallen from
$2.6 billion annually to $1 billion- and expected to fall even further
as major food processors, supermarkets, and fast-food chains ban GM soya
or soya derivatives in animal feeds. Canada's canola exports to Europe
similarly fell from $500 million a year to near zero. From Biodemocracy
News #27 www.purefood.org
- See Ho, M.W. (1998). The
Rainbow and The Worm, The Physics of Organisms, 2nd ed., World
Scientific, Singapore; Ho, M.W. (1998, 1999). Genetic
Engineering Dream or Nightmare? Gateway, Gill & Macmillan,
Dublin.
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