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Re: Biotechnology - Part II



SANETTERS - continuation of Part I.

Other issues raised from the scientific literature reviewed in the 
book Ecological Effects of Genetically Engineered Organisms:

3.  Exotic, "introduced" species - of which GEO's will be just one 
example - have a long and well documented history of becoming "pests" 
in their new home.  A recent issue of the journal Consequences 
presented an authoritative review of just how often an introduced 
species - whether it be plant, microbe, or animal - becomes pest-like 
in a new environment (e.g. red deer in NZ; purple loosestrife in 
Canada).  In many respects, a pest could be defined as an organism 
that is "out of context", out of range of the "controls" (e.g. its own 
predators, pathogens, competitors) which regulated its density in its 
zone of origin.  It is not simply possible, but probable, that at 
least some GEO's will behave as introduced species have already done 
and become pests, with unimaginable outcomes.  

The key point to note is that the introduced pests were not pests in 
their zone of origin - they became pests in their new home.  For 
GEO's, the zone of origin could be considered the field test sites 
which have already been used to authorize release.  It is not 
possible to predict how the GEO's will behave outside of those test 
sites, just as it is not possible to predict how an introduced 
species will behave outside of its zone of origin.  And be clear as 
well that this effect is different from and unrelated to the 
implications of gene transfer from the transgenic crop to other 
species.  This effect accrues to the original GEO itself.

4.  The method by which a researcher determines if s/he has been 
successful in introducing new genes into a novel genome is to place 
the new genes on a bit of DNA (or RNA, etc.), TOGETHER with a marker 
gene, and then insert the bit of DNA into the new host DNA (my 
apologies to those of you who would word this more scientifically, 
but this is the sense of the process).  The marker gene is most 
often a gene conferring resistance to some common antibiotic.  Then, 
the researcher plates out the prospective new host cells on a medium 
containing the antibiotic, and those that survive are those which 
successfully integrated the new bit of DNA into their own DNA.  Slick 
and easy screen.

What this means in practice is that every time you bite into a Flavr 
Savor tomato (if you somehow know it is a Flavr Savor tomato, 
because the company owning this product was successful in 
preventing labelling of this GE tomato to allow consumers to make 
an informed choice), you are ingesting genes for antibiotic 
resistance.  For some years, proponents of these products have said 
that this was not a problem, because the genes would be digested in 
the stomach - end of story.  Newer evidence, published I believe in 
Nature or Science within the last year, found otherwise.  Just as 
we scientists can excise out and reinsert little bits of DNA (RNA, 
etc.) to make transgenic plants, so too the bits of DNA can be 
subsequently released and reinserted into new, unintentional host 
cells - like an E. coli cell in your child's stomach.   The risk is 
small - granted - but not negligible.  

Do the benefits of FlavrSavor genes (or BST-stimulated milk in cows, 
or Bt corn, or.......) outweigh the implications of distributing 
antibiotic resistance genes not simply into our own digestive tracts 
but into the the whole agroecosystem?  

5.  Are the products of genetic engineering actually needed in the 
first place, and what are their implications for the environment and 
society as a whole?  Some 90% of the transgenic crop research underway 
in Canada involves identifying and inserting herbicide resistance 
genes into crop plants.  Is there any reason to think that the same, 
long known and very well documented pattern of resistance development 
in target organisms (e.g. DDT and gnats in CA; Colorado potato 
beetles and everything, everywhere; triazine resistance in major 
weeds, etc.) will NOT happen - and faster - when the genes for 
resistance are actually present in the crop plants themselves?  The 
selection pressure exerted by the presence of resistance genes in 
hundreds of thousands of hectares of a given crop would be enormous.  


Who is the net beneficiary of this line of thinking?  Producers?  
Consumers?  The environment?  Who?  

In sum, the foregoing is meant to provide evidence - 

    hard scientific evidence of the sort published in respected, peer 
reviewed journals, not fabricated by wild-eyed misguided activists 
whipping up hysteria in an ill-informed consuming public (this is how 
the argument is usually framed) 

- to challenge the thesis that biotechnology is a valuable tool in 
the genetic improvement of crops and livestock.  

Indeed, the converse seems much more likely.  It seems not 
implausible to me that people will soon look back and wonder at the 
ecological naivete and unfettered optimism that allowed biotechnology 
to rise to prominence in this era of agricultural research.  Ann






ACLARK@crop.uoguelph.ca
Dr. E. Ann Clark
Associate Professor
Crop Science
University of Guelph
Guelph, ON  N1G 2W1
Phone:  519-824-4120 Ext. 2508
FAX:  519 763-8933