GENTECH archive


Fw: toxins GEd into potatoes

>Here is an exchange between an antagonist of Dr Pusztai (a David Wengraf of
>the UK) and a New Zealand scientist critical of GE.
>>The point I was trying to make was that a toxin was engineered into the
>>potatos, which was what made the rats sick, not the fact that the potatoes
>>were engineered.
> but then the immediate next point is that the engineering which is
>being done on potatoes is in many cases for a similar purpose, viz.
>introducing a constitutive toxin.  Our government has recently permitted
>(over our strenuous objections) millions of possible GEd potato constructs
>with various toxins from the African clawed toad, the giant silkworm,  etc
> What meaning would you attach to the phrase "the fact that the
>potatoes were engineered" other than actual biochemical differences such as
>these proposed alterations or Pusztai's changes?  That is a straight, not
>at all a rhetorical, question.  The engineering is for the declared purpose
>of producing biochemical differences which, contrary to vague PR images,
>are not of clear toxicological significance.  The only way to assess the
>actual toxicological significance of such constructs is by testing them on
>many generations of the target mammals  -  and that cannot be done,
>ethically, so rodents must serve.  It is one of the big lies of the gene
>jockeys that they can foresee the effects of their transpositions.
>Empirical testing is therefore essential.  And you do not have to be an
>'animal rights' fanatic to wonder why many rodents should be sacrificed for
>this, when the original purpose of the GE is dubious anyhow.  The problems
>for which the GEd spuds are proposed are in most if not all cases trivial
>and have known remedies.  In that regard I should point out that the
>apparent contradiction of this in the article copied below is mere humorous
>exaggeration; our inquiries with the potato growers' federation revealed
>that bacterial rot occurs only rarely - only in either incompetent storage
>or unsuitable (over-wet) growing conditions.
> I am of course interested, as a rtd academic, that you are doing a
>thesis related to our topic of mutual interest.  I hope you get hold of the
>'phoenix from the pulping' number of The Ecologist, which is almost
>completely reliable (certainly far more so than the GE PR on which I attach
>some general background info).
> Your desire to "see some science on the issue" is wholly shared by
>those here who also see that science cannot be the whole story.
> I copy below a very good article by one of our scientists.
>note added for foreigners
>katipo: NZ's only poisonous spider
>kumara: sweet 'potato', a main food for the classical Maori and still
>popular with most New Zealanders
>possum: the introduced brush-tailed marsupial outnumbering humans 20:1 - a
>grave forest pest and   vector of bovine TB
> New Zealand Herald 3-12-98
>Genetic engineers are about to learn whether they will be allowed to slip
>synthetic toad genes into potatoes.  PETER WILLS says we should be
>concerned about these experimental programmes.
>Last month the new Environmental Risk Management Authority (ERMA) held
>hearings in Wellington about a proposal from the Institute for Crop and
>Food Research to grow plots of potatoes containing a synthetic gene that
>encodes an antibiotic toxin from the African clawed toad.  The experimental
>programme is designed to discover whether production of the toad antibiotic
>in potatoes protects them against the troublesome soft rot that plagues
>growers and distributors.
>Most people are unaware of how easy genetic engineering has made it to mix
>and match genes from creatures belonging to completely different biological
>kingdoms.  And when they are told about it they are assured that the
>process is really no different from the techniques of selective breeding
>which humans have been engaging in for thousands of years.
>Genetic engineering speeds up the process and is much more precise, we
>Crop and Food scientists are sure that potatoes lack something very
>important and desirable - genes that confer resistance to soft rot.  But
>not to worry, they have set that right using information that can be found
>on the internet about the gene from the African clawed toad, and now the
>genetic diversity of potatoes has been increased by the addition of a
>synthetic gene encoding the toad toxin.  They even describe the synthetic
>gene as a new potato gene.
>ERMA has to decide whether Crop and Food should be allowed to grow plots
>containing 150 different lines of genetically modified potatoes during each
>of the next five years.  Some of the spuds are to produce a toxin found in
>giant silk moth rather than the toad, others an enzyme from a "phage", a
>sort of virus that attacks bacteria, and still others Bt insecticide toxins
>derived from the bacterium which was used to great effect in Auckland
>against the white-spotted tussock moth.
>The application from Crop and Food stated that all the transgenic potato
>lines were produced essentially following their standard transformation
>protocols, but it turns out that most of the potatoes, perhaps three or
>four hundred different varieties, have not yet been produced at all.  The
>Institute's legal counsel argued that an application under the new
>Hazardous Substances and New Organisms (HSNO) Act was like a request for a
>discharge under the Resource Management Act.  You shouldn't have to specify
>every occasion on which you are going to discharge waste, or the exact
>composition of the waste, provided the levels of chemicals are within
>certain limits.  So, they argue, you shouldn't be required to have already
>created all the modified potatoes you want to grow.
>One of the problems with currently available techniques for genetic
>engineering is that when you introduce a new gene into an organism, the DNA
>can become inserted at essentially any point in the organism's chromosomes.
>The genetic engineer lets this happen more or less at random and then
>looks for transformed organisms that seem to behave normally, those whose
>genetic structure has probably not been seriously disrupted by introduction
>of the new foreign gene.  The Crop and Food application is designed to
>cover billions of such possibilities.
>It is not possible to test many important characteristics of transformed
>potatoes before they are field tested in open experimental plots.  For one
>thing, potato plants don't usually flower when grown in a containment
>glasshouse.  This means there is considerable uncertainty concerning the
>possible characteristics of modified potatoes even after they have been
>produced and grown in containment.  However blanket approval is being
>sought to grow open plots of potato lines that haven't yet been created,
>let alone met the limited tests of normality that can be conducted in a
>No-one denies that the proposed experiments run a risk of "genetic escape"
>but the probability of the toxin genes being transferred into other
>organisms in the wild is claimed to be minuscule.  It is up to ERMA to
>decide whether the benefits of the experiments outweigh the risks.  In
>making their judgment, the HSNO Act directs them to "take into account the
>need for caution in managing adverse effects where there is scientific or
>technical uncertainty".  This is an expression of the precautionary
>principle that was incorporated into the 1992 Rio Declaration on
>Environment and Development.
>What approach would New Zealanders like to see ERMA adopt in reaching its
>decision?  A special advisory group, Nga Kaihautu Tikanga Taiao, has been
>set up to look after Maori interests and comment on Treaty issues.  The
>group noted in its report that some of the general concerns about genetic
>engineering raised in public submissions to ERMA were similar to those
>likely to be raised by Maori, but tangata whenua cannot be lumbered with
>the task of acting as a conscience for the whole of society.
>The Maori attitude to indigenous flora and fauna obviously differs from the
>attitude of scientists to "biodiversity", as the living world is now called
>in official circles.  If I sequenced the gene encoding the katipo toxin,
>inserted a modified version into kumara which I then wanted to grow in
>experimental plots with a view to testing the vegetables as possum bait,
>great weight would be given to the statutory role of Nga Kaihautu in
>protecting the status of katipo and kumara as taonga.  However genetic
>engineers do not regard the provenance of evolution as a treasure, the
>integrity of which they have a responsibility to preserve.  In New Zealand
>we allow the transfer of genetic information from the African clawed toad
>into potatoes to be carried out in an ethical void.
>We are all complicit.  While tangata whenua act to protect and preserve the
>whakapapa of their valued taonga, we allow genetic engineers to reduce the
>evolutionary tree of life to a jumbled heap of broken twigs.  In fact, the
>government is right behind such activity and foreign corporations are given
>liberal access to New Zealand as a testing ground for their genetically
>engineered products.
>When scientific and technological innovation produces applications with
>far-reaching social, political and economic consequences, all sorts of
>ethical questions that need careful consideration and debate come to the
>fore.  At the very least, ERMA needs an Ethics Committee, analogous in its
>mode of function to Nga Kaihautu, which can advise on the attitude of New
>Zealanders to a range of questions concerning the effects of genetic
>engineering.  More desirable, and in addition, we should have a full public
>enquiry, a Royal Commission, before whom members of the public can express
>their attitudes about modern biotechnology.  In the meantime, as a
>precautionary measure, we should declare a moratorium on the release of all
>genetically modified organisms into the environment.
> * * * *
>Dr Peter Wills is an associate professor, Department of Physics, University
>of Auckland


>Dr Robt Mann
>science chairman, Physicians & Scientists For Responsible Genetics
>P O Box 28878 Remuera, Auckland 1005, New Zealand
> (9) 524 2949