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March 28, 2000
The Boston Globe
Should we worry over genetically altered foods?
In the early 1990s, while almost nobody was looking, the biotech industry,
according to this story, pulled off quite a coup. Led by industry giants
like Monsanto, DuPont, Novartis and Aventis, genetic engineers began
commercializing an idea they'd worked on for years - tinkering with genes
to
make crops more resistant to insects and herbicides. The basic idea was
clever. If, say, a gene could be inserted into soybean seeds so the plants
would be resistant to an herbicide, farmers could spray their fields with
that herbicide, killing the weeds without fear that it would harm the
cash
crop. If a gene could be introduced into corn that would produce a protein
toxic to corn-eating caterpillars, farmers could grow that kind of corn
without using high quantities of pesticides. The idea has not only worked
-
it's worked too well in the eyes of the anti-biotech crowd, which has
been
staging counter-demonstrations this week in Boston during BIO2000, the
biotech industry's annual gig.
The story says our digestive enzymes should chew up GM food the same way
they process everything else we eat and that, among other things, that
means
that it's unlikely that, say, a gene from a flounder that's inserted into
a
tomato (as scientists are doing to make tomatoes more resistant to freezing)
would somehow lodge itself forever in the human genome. In fact, if it
were
that easy to transfer genes, scientists wouldn't have to resort to
sophisticated tricks to create transgenic animals in the lab: They could
just feed them GM food. Indeed, there's no evidence that any human has
ever
been harmed by eating GM food. (This is in contrast, by the way, to evidence
that some herbal products, which people assume are safe because they're
''natural,'' can be harmful.) Given that 60 percent of the processed food
now on the American market contain ingredients that have been genetically
engineered (a fact many people don't realize), chances are that if the
stuff
were dangerous, somebody would have noticed. But none of this is what
really
irks consumers - including this one - on both sides of the Atlantic.
What is irksome, the story says, is that, even though GM foods may be
safe,
there's too little testing to say for sure - and there are no labels to
guide us. We don't know, for instance, whether the proteins made by genes
inserted into plants could cause serious, even fatal, allergic reactions.
In
one notorious case, scientists inserted a Brazil nut gene into soybeans
to
increase protein. When the hybrid was lab tested in 1996, human antibodies
reacted to the nut gene, a sign that the product could have caused allergies
in people. Martin Teitel, executive director of the Council for Responsible
Genetics, a Cambridge-based watchdog group, was quoted as saying,
''Bioengineering could produce novel protein combinations that the human
body has never seen before, potentially resulting in serious allergies
that
would be difficult to diagnose.''
Another concern is that gene-altered foods may have different nutrient
value
than standard foods. Though the biotech industry disputes it, GM soybeans
may have fewer phytoestrogens than normal, a potentially important change,
since some consumers eat soybeans precisely to get the hormone-like effects
of these plant estrogens. Opponents of GM foods also worry that gene-altered
crops might contain pesticide residues or, worse in the eyes of some
opponents, genes that make pesticides in every cell in the plant. (On
the
other hand, with some gene-altered crops, farmers can use fewer pesticides
than normal.) And then there's the concern that these crops could increase
antibiotic resistance. Bioengineers use antiobiotic-resistance genes as
markers to see whether the genes they put into plants get into the DNA.
The
worry is that eating the altered food could allow the marker genes to
pass
into bacteria in the human digestive system, making people resistant to
potentially life-saving antibiotics.
Val Giddings, a geneticist and vice president for food and agriculture
at
the Biotechnology Industry Organization in Washington, was quoted as saying,
''That argument is totally bogus for two reasons. Number one, the antibiotic
resistance genes used as markers in biotech do not [cause] resistance
to
antibiotics used to treat human disease. Number two, those resistance
genes
are already present in the human digestive tract.'' Furthermore, ''crops
improved by biotechology have been subjected to more scrutiny in advance,
depth, detail and rigor than any other foods introduced into the food
supply
in human history.''
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