The SCD™ Knowledge Base

Genetically Modified and Engineered Food

Annie The Axe, our resident Eco-warrior-maiden, sends in this:
GM GENES COULD PROVE HARD TO STOMACH
British scientific researchers have found that genetically modified DNA
material from crops is finding its way into human gut bacteria, the
Guardian reports. It says the GM material poses no health problems but
antibiotic resistant marker genes in the plants could compromise
antibiotic resistance among humans.
* GM genes found in human gut
http://www.guardian.co.uk/gmdebate/Story/0,2763,756666,00.html
And my personal favorite of Annie's contributions to the GM discussion:
BRAVE NEW NATURE
A Nation of Lab Rats
Is genetically engineered food bad for you? Maybe. Maybe not.
by Barbara Keeler
If it's true that you are what you eat, now would be the time to start
scrutinizing the fine print. Just five years after genetically engineered
foods were quietly introduced into the marketplace, gene-manipulated soy,
papaya, yellow-neck squash, canola, potatoes, tomatoes, and dairy and
animal products are on the tables of consumers, with another hundred or
so, including wheat, expected soon. According to most estimates, 60 to 70
percent of all processed foods contain genetically modified ingredients.
But there is no fine print. Food regulations in the United States don't
require segregation or labeling of genetically engineered products. The
Food and Drug Administration presumes that genetically engineered foods
are substantially the same as their unmodified counterparts. But Health
Canada (the FDA's Canadian equivalent), the UN Food Safety Agency, and the
United Kingdom's Ministry of Agriculture have all questioned the safety of
certain genetically engineered foods, especially dairy products from cows
treated with recombinant bovine growth hormone, or rBGH. Last year, the EU
declined to approve Monsanto's Roundup Ready corn for human consumption
because of concern about potential allergic reactions. Roundup Ready corn
and soybeans are ubiquitous in the U.S. food supply, despite Monsanto's
own study for the FDA, which revealed large differences in nutrients and
allergens between its modified and unmodified soybeans.
To understand the potential problems, you first have to understand the
process by which geneticists hope to imbue a living organism with new
characteristics, such as herbicide resistance. Scientists pluck a gene
from another species (a "transgene") that carries the desired trait. But
the transgene does not travel alone. It generally rides in on a "truck" of
bacterial DNA, loaded with baggage and sometimes unsuspected stowaways.
Even if the transgene comes from a related plant species, bacteria, virus,
and antibiotic-resistant genes are usually packaged in as delivery
systems, "on switches," or markers.
Whether transgenes are introduced into a cell of a host plant using
bacteria or a "gene gun" (a process in which gold or tungsten
micro-particles are coated with transgenes and then fired into targeted
cells or tissues), they cannot be directed to a specific location on the
host chromosomes or even to a specific chromosome. Incorporation into the
host DNA is more or less a crapshoot, and only a small percentage of cells
end up with the transgenes. To figure out what's ended up where,
scientists link marker genes that are resistant to antibiotics or
herbicides, then kill off all cells except those with the resistance
markers and allow the transformed cells to grow into intact organisms.
Voilà, a pest-resistant zucchini. Well, maybe--and maybe things unexpected
as well.
Without segregation of genetically engineered products and post-market
monitoring, the long-term impacts on human health of, for example, the
cauliflower mosaic virus (a virus used to assist the process as a
"promoter") are impossible to monitor. But we've already had warnings of
genetic engineering's potential impact on antibiotics resistance,
naturally occurring allergens, and healthy human cells, some of them from
the FDA's own literature. For example:
The FDA warns of decreased effectiveness of antibiotics due to
antibiotic-resistant marker genes incorporated into genetically modified
organisms and their enzyme products. The UK Ministry of Agriculture
cautions that antibiotic-resistant genes in modified corn could render
useless eight powerful antibiotics used by doctors to fight fatal
diseases.
According to the FDA, "many plants naturally produce a variety of
compounds that are toxic to humans or alter food quality. Generally, these
are present at levels that do not cause problems. Combining plant and
animal species in genetic engineering may create new and much higher
levels of these toxins." Corn and potatoes engineered to produce toxins
that kill insects are already regulated by the EPA as pesticides.
The FDA also warns that genetic engineering could transfer new and
unidentified proteins from one food into another, triggering allergic
reactions: "Millions of Americans who are sensitive to allergens will have
no way of identifying or protecting themselves from offending foods.
Allergic reactions can cause more than a simple discomfort--they can
result in life-threatening anaphylactic shock." A study by the UK's York
Nutritional Laboratory, Europe's leading specialist on food sensitivity,
revealed a 50 percent increase in soy allergies in 1998, a period in which
the percentage of genetically engineered beans in the total soy crop
jumped dramatically. For the first time in 17 years of testing, soy ranked
among the top ten allergenic foods. Soybeans naturally contain at least 16
proteins that can cause allergic reactions, and one was found in almost 30
percent higher concentrations in Monsanto's transgenic soybeans. Rats
eating those soybeans experienced retarded growth, and cows showed altered
fat levels in their milk.
Canadian and European authorities recommended against eating foods from
cows treated with rBGH after finding evidence of potential cancer hazards:
Rats absorbed the hormone and developed immunological reactions, thyroid
cysts, and prostate abnormalities. Cow's milk contained elevated levels of
the hormone IGF-1, linked by research to increased cancer risk in humans.
Even so, some U.S. dairy farmers--primarily industrial-scale
operations--still inject their cows with rBGH.
As long as genetically engineered foods remain largely unregulated and
products unlabeled, the causes and effects of those abnormalities may
remain a mystery. The only comprehensive experiments may be under way at
your dinner table.
Barbara Keeler writes about health, environmental, and regulatory issues.
http://www.sierraclub.org/sierra/200107/keeler.asp

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