Posted
20th August 2001
Beans Not Genes Please
The world's most widely grown genetically engineered crop contains
some unexpected DNA next to its inserted gene, casting some
doubts on the biotechnology industry's assertions that its technology
is precise and predictable.
The
mysterious DNA was found in the Monsanto Company's Roundup Ready
soybeans by Belgian government and university scientists, who
described their findings in a paper published yesterday in the
journal European Food Research and Technology. Greenpeace called
yesterday for countries to re-evaluate the regulatory approvals
of the soybeans, saying that Monsanto did not know as much as
it should about its product. The unknown DNA could possibly
affect the safety of the beans, the group said. "I don't think
you can come out and say it's unsafe," said Dr. Janet Cotter-Howells,
a scientist for Greenpeace in Britain. "You can just say it's
unknown whether it's unsafe or not."
Monsanto acknowledged that the extra DNA was there, but it said
it was confident that the soybean was safe and that the unknown
DNA had no effect on the plant. Dr. Jerry J. Hjelle, the company's
vice president for regulatory affairs, said the DNA segment
had been in the crop since the beginning as it went through
testing to prove its safety. Products made from Roundup Ready
soybeans have been eaten by people and animals for five years
with no reports of health problems. Still, the findings could
cause some embarrassment for Monsanto and the agricultural biotech
industry because they raise questions about how well the molecular
makeup of the products is characterized. Roundup Ready soybeans
contain a gene from a bacterium that allows the plants to withstand
Monsanto's Roundup herbicide. Farmers can thus spray their fields
with Roundup throughout the growing season to kill weeds without
harming the crop. More than half the soybeans grown in the United
States are now Roundup Ready. In Europe and Japan the beans
are approved for use but not for planting.
This
is the second time that scientists have found something in Roundup
Ready soybeans that Monsanto did not seem to know was there
and had not cited at the time of the product's approval. Last
year the Belgian scientists and Monsanto, working independently,
found that the soybeans contained not only one complete copy
of the bacterial gene, as intended, but two fragments of that
gene. Monsanto filed reports with regulators around the world
offering data to show that the fragments were not active genes
and had no effect on the plant. The paper now being published
contains another revelation. Adjacent to one of those gene fragments
is another stretch of DNA that Monsanto, in its report to regulators
last year, had assumed was the soybean's native DNA.
But the Belgian scientists, led by Dr. Marc De Loose of the
Center for Agricultural Research in Melle, said they could not
find this stretch of DNA in the soybean that had not been genetically
engineered. They suggested that this unknown DNA is probably
the plant's own DNA but that it was somehow rearranged, or scrambled,
at the time the bacterial gene was inserted. Another possibility,
they said, is that a portion of the plant's DNA was deleted,
leaving other DNA in that position.
Dr.
Hjelle, of Monsanto, said that the new paper by the Belgian
scientists had been available online for some time and that
Monsanto had already discussed the information with regulators.
He said the unexpected DNA had been found because more sensitive
techniques had made it practical for the first time to determine
the sequence of the DNA flanking the inserted gene. "As methods
improve," he said, "we can find things from a detailed perspective
that we couldn't 10 years ago." Dr. Hjelle said the unknown
sequence was only 534 letters long out of a soybean genome of
about 1.5 billion letters and was not meaningful. He also said
that the jumbling up of DNA near the spot where a new gene was
inserted was "expected by people who understand the science."
Dr. David Ow, a senior scientist at the Department of Agriculture's
Plant Gene Expression Center in Albany, Calif., said that an
inserted gene did not always integrate itself into a plant in
a neat way. "It's not so much that rearrangements occur, but
what are the consequences of it?" he said. Dr. Ow said he did
not think that this would pose a public safety issue, but he
said it would pose a public perception problem for the industry.
"If one is submitting a product it has to be characterized to.
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