> I think the concern is with the unknowns of cross-species involvement. When
> you play with the basic genetic structure, the results are still quite
> unpredictable.
I'd like to reinforce that point with something that I don't think has been
well discussed as yet on SANET. Several have referenced the notion of
horizontal gene transfer, which is a wholly normal thing for procaryotic
creatures (do they still use that term? I may be out of date. I mean the
single celled guys that do not have specialized tissues, as for reproduction).
Bacteria and suchlike organisms routinely and normally exchange bits of DNA in
their version of sex (e.g. conjugation, transformation etc.) to achieve genetic
recombination. Nothing new or startling about that.
But as has been mentioned at least a few times on SANET, new genes behave
unpredictably in new genomes, particularly when accompanied by their little
promoter buddy snips etc. (e.g. the example of the gene for herbicide
resistance affecting a wholly unrelated trait - outcrossing - in Arabadopsis
thaliana; the thesis that the cauliflower mosaic virus promoter genes for the
snowdrop lectin gene - and not the lectin gene itself - may have caused the
abnormalities that Pusztai saw in his rats at the Rowett). So, while the
material coding for Bt, for example, may be horizontally transferred into the
genome of a fungus (there is published evidence of transgene movement into
Aspergillus niger (a common decomposer fungus) following incorporation of
transgenic plant material into the soil), the "risk" of this event is not
simply "what will the Bt genes/buddies do in the fungus genome". Rather, what
*other* fungal genes might be affected by the Bt/promoter genes? Or in another
fungus, bacteria, or protozoan organism that, in turn, receives the same genes
by a second horizontal transfer or a third or..... And remember, the "effect"
may be simply from the promoter buddy increasing the activity of *another* gene
(not the transgene), like putting out more of compound X . Let's say that
compound X is something which is normally expressed at subtoxic or
sub-allergenic levels in the recipient organism but following gene transfer,
could increase to toxic or allergenic proportions (this is a food safety
speculation; I have no evidence of this).
And keep in mind too, the *scale* of potential horizontal transfers when every
cell of every plant in every hectare of 10s of millions of hectares, every
year, contains the same Bt/buddy construct.
Given the foregoing, which I believe is scientifically defensible and already
documented in the refereed literature (unlike the food safety studies we hear
so much about), on what conceivable basis can anyone, even the august Pioneer,
presume to tell us that there is no risk? As stated by David Suzuki regarding
claims of food safety testing in Canada ( he is a very well known molecular
geneticist turned science communicator), such a contention could only come from
someone who is "very stupid or lying". Or perhaps just nearsighted.
To illustrate this point, I once used the example of a dairy producer who could
walk out into a herd of 100 cows and even without ear tags, tell you everything
you could possibly want to know (and usually a lot more) about each and every
one. To those not of the dairy persuasion, they are just "cows", but a dairy
producer can distinguish the animals in their own herd - based on markings,
conformation, behavior, and other attributes - because they have the "eyes" to
see.
I would put it to you that at least part of the reason Dale and others are
disinclined to accept even the potential of a risk from GE (such as that laid
out above) is because their training/experience/colleagues have put blinkers or
filters on their vision. Someone (Pasteur?) once said that "discovery comes to
the prepared mind". By analogy, to a mind that is not ready - for whatever
reason - to "see" GE risks, all of this discussion is much ado about nothing.
Now, it is fair to say that the above evidence is only in a few papers, but why
is that? Does the small number of papers reflect the uniqueness or unusualness
of the problem, or rather, the perishingly small amounts of research funding
for those seeking to explore these issues? On what basis can one conclude the
former, as many industry proponents already have, without refereed publications
showing that these phenomena (horizontal gene transfer and unpredictable side
effects) do NOT occur? In the absence of such publications, such a conclusion
is at best premature, and at worst, subjective, self-serving, and
scientifically indefensible. Ann
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