Hazardous GMO warning sign |
Back in October, a group of Australian
scientists published a warning to the citizens of the country, and of
the world, who collectively gobble up some $34 billion annually of its
agricultural exports. The warning concerned the safety of a new type of
wheat.
As Australia’s number-one export, a
$6-billion annual industry, and the most-consumed grain locally, wheat
is of the utmost importance to the country. A serious safety risk from
wheat — a mad wheat disease of sorts — would have disastrous effects for the country and for its customers.
Which is why the alarm bells are being
rung over a new variety of wheat being ushered toward production by the
Commonwealth Scientific and Industrial Research Organization (CSIRO) of
Australia. In a sense, the crop is little different than the wide
variety of modern genetically modified foods. A sequence of the plant’s
genes has been turned off to change the wheat’s natural behavior a bit,
to make it more commercially viable (hardier, higher yielding, slower
decaying, etc.).
What’s really different this time — and
what has Professor Jack Heinemann of the University of Canterbury, NZ,
and Associate Professor Judy Carman, a biochemist at Flinders University
in Australia, holding press conferences to garner attention to the
subject — is the technique employed to effectuate the genetic change. It
doesn’t modify the genes of the wheat plants in question; instead, a
specialized gene blocker interferes with the natural action of the
genes.
The process at issue, dubbed RNA
interference or RNAi for short, has been a hotbed of research activity
ever since the Nobel Prize-winning 1997 research paper that described
the process. It is one of a number of so-called “antisense” technologies
that help suppress natural genetic expression and provide a mechanism
for suppressing undesirable genetic behaviors.
RNAi’s appeal is simple: it can
potentially provide a temporary, reversible “off switch” for genes.
Unlike most other genetic modification techniques, it doesn’t require
making permanent changes to the underlying genome of the target.
Instead, specialized siRNAs — chemical DNA blockers based on the same
mechanism our own bodies use to temporarily turn genes on and off as
needed — are delivered into the target organism and act to block the
messages cells use to express a particular gene. When those messages
meet with their chemical opposites, they turn inert. And when all of the
siRNA is used up, the effect wears off.
The new wheat is in early-stage field trials (i.e.,
it’s been planted to grow somewhere, but has not yet been tested for
human consumption), part of a multi-year process on its way to potential
approval and not unlike the rigorous process many drugs go through. The
researchers conducting this trial are using RNAi to turn down the
production of glycogen. They are targeting the production of the wheat
branching enzyme which, if suppressed, would result in a much lower
starch level for the wheat. The result would be a grain with a lower
glycemic index — i.e., healthier wheat.
This is a noble goal. However, Professors
Heinemann and Carman warn, there’s a risk that the gene-silencing done
to these plants might make its way into humans and wreak havoc on our
bodies. In their press conference and subsequent papers, they describe
the possibility that the siRNA molecules — which are pretty hardy little
chemicals and not easily gotten rid of — could wind up interacting
with our RNA.
If their theories prove true, the results
might be as bad as mimicking glycogen storage disease IV, a super-rare
genetic disorder which almost always leads to early childhood death.
Although Heinemann and Carman cannot
provide rock-solid proof that the new wheat is harmful, they have
produced a series of opinion papers that point to the possibilities that
could happen if a number of criteria are met:
- If the siRNAs remain in the wheat in transferrable form, in large quantities, when the grain makes it to your plate. And…
- If the siRNA molecules interfere with the somewhat different but largely similar human branching enzyme as well…
Then the wheat might cause very severe adverse reactions in humans.
Opinion papers like this — while not to
be confused with conclusions resulting from solid research — are a
critically important part of the scientific process. Professors Carman
and Heinemann provide a very important public good in challenging the
strength of the due-diligence process for RNAi’s use in agriculture.
However, we’ll have to wait until the
data come back from the numerous scientific studies being conducted at
government labs, universities, and in the research facilities of
commercial agribusinesses like Monsanto and Cargill — to know if this
wheat variety would in fact result in a dietary apocalypse.
But if the history of modern agriculture
can teach us anything, it’s that GMO foods appear to have had a huge net
positive effect on the global economy and our lives. Not only have they
not killed us, in many ways GMO foods have been responsible for the
massive increases in public health and quality of life around the world.
Nevertheless, the debate over genetically
modified (GM) food is a heated one. Few contest that we are working in
somewhat murky waters when it comes to genetically modified anything. At
issue, really, is the question of whether we are prepared to use the
technologies we’ve discovered.
In other words, are we the equivalent of a
herd of monkeys armed with bazookas, unable to comprehend the sheer
destructive power we possess yet perfectly capable of pulling the
trigger?
Or do we simply face the same type of
daunting intellectual challenge as those who discovered fire,
electricity, or even penicillin, at a time when the tools to fully
understand how they worked had not yet been conceived of?
In all of those cases, we were able to
probe, study, and learn the mysteries of these incredible discoveries
over time. Sure, there were certainly costly mistakes along the way. But
we were also able to make great use of them to advance civilization
long before we fully understood how they worked at a scientific level.
Much is the same in the study and practical use of GM foods.
While the fundamentals of DNA have been
well understood for decades, we are still in the process of uncovering
many of the inner workings of what is arguably the single most advanced
form of programming humans have ever encountered. It is still very much a
rapidly evolving science to this day.
While RNAi is not a panacea for GMO
scientists — it serves as an off switch, but cannot add new traits nor
even turn on dormant ones — the dawn of antisense techniques is likely
to mean an even further acceleration of the science of genetic meddling
in agriculture. Its tools are more precise even than many of the most
recent permanent genetic-modification methods. And the temporary nature
of the technique — the ability to apply it selectively as needed, versus
breeding it directly into plants which may not benefit from the change
decades on — is sure to please farmers, and maybe even consumers as
well.
That is, unless the scientists in
Australia are proven correct, and the siRNAs used in experiments today
make their way into humans and affect the same genetic functions in us
as they do in the plants. The science behind their assertions still
needs a great deal of testing.
Still, their perspective is important
food for thought… and likely fuel for much more debate to come. One
thing is sure: the GMO food train left the station nearly a century ago
and is now a very big business that will continue to grow and to innovate, using RNAi and other techniques to come.
Source: www.dailyreckoning.com
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