Newsweek Covers the Mexican
Corn Controversy

Newsweek
January 28, 2002The Tale of the Mystery Corn in Mexico's Hills

BY: By Alan Zarembo

A researcher's discovery embarrasses the government, strikes fear in farmers
and reignites a scientific debate

Olga Toro Maldonado was short on corn seed and slightly curious. In the
spring of 1998, alongside the corn she had always raised on her hillside
plot, she planted 60 kernels purchased from the government store. "The corn
looked good," she recalls, so the next year she planted a cross between the
two species. The harvest was smaller than the year before--one ear per stalk
rather than the usual two--but the corn was tasty enough. She ground it into
flour for tortillas and fed the kernels to her chickens.

A few scientists stopped by in fall 2000 and took away samples from her most
recent harvest. They returned a week later with some disturbing news. Toro's
corn contained transgenes--genes from bacteria and other organisms
artificially introduced into the corn to make it resistant to herbicides or
insects. Toro, 40, heard the word "contamination" and began worrying about
her six children, her chickens and whether the pollen from her corn had
spread. "I feel guilty," she says. "But another woman told me she planted
it, too. I'm not the only ignorant one. We don't know the damage we can do."
The head scientist was Ignacio Chapela, a 42-year-old Mexican and a
microbial ecologist at the University of California, Berkeley. His team
collected corn from the mountains of Oaxaca, in southern Mexico, and found
that several samples contained transgenes. The finding was startling because
the Mexican government bans the planting of genetically modified (GM) corn.
And the agriculture industry has long contended that contamination from GM
crops was extremely unlikely. "I was dumbfounded," Chapela says. "I knew it
was a difficult political fray we were getting ourselves into."

There is no evidence that GM corn is dangerous for human consumption.
Chapela and his allies are concerned instead that GM corn might pose a
threat to corn's biodiversity. Mexico, where corn was first domesticated
10,000 years ago, is what scientists call the crop's "center of genetic
diversity"--a kind of repository of traditional varieties. GM corn, with its
engineered advantages, could theoretically overwhelm these indigenous types.
That would leave breeders without a source of pristine seed if a plague
struck corn crops elsewhere. "World food security depends on the
availability of this diversity. Having it contaminated is something humanity
should worry about," says Chapela.

Mexico, the corn-consuming capital of the world, has been cautious about
corn. Congress banned GM corn crops in 1998 even while allowing GM cotton
and tomatoes. The current administration has been considering loosening the
ban in an effort to improve agriculture and attract investment. A
combination of decades of bad agricultural policy and falling trade barriers
with the United States has turned Mexico into an importer of its staple
food: 6 million tons of corn a year come from the United States. A panel of
scientific advisers recently recommended opening northwest Mexico, which has
none of the traditional strains of corn, to transgenic corn crops. "Mexico
as a country cannot exclude itself from biotechnology," says Victor Manuel
Villalobos, the under secretary of Agriculture. "It is not an intelligent
position to say that because there are risks we won't touch it."
Chapela's revelation that GM corn is already growing in the hills of Oaxaca
is an embarrassment to the Mexican government, to say the least. After
Chapela's paper appeared in the scientific journal Nature in November, a
Greenpeace activist declared the contamination "a worse attack on our
culture than if they had torn down the cathedral of Oaxaca and built a
McDonald's over it." The group began urging indigenous groups in Oaxaca to
sue the federal government. Eighty scientists from 12 countries demanded the
government take steps to contain the damage.

The government's own tests found transgenes in Oaxaca and neighboring
Puebla, as had Chapela, but Villalobos maintains that more detailed studies
now underway may very well refute Chapela's findings. Meanwhile, he warned
Chapela in a letter dated Nov. 28 that the federal government "will take
measures... to redress the great damages, as much to agriculture as to the
economy in general, that... your publication might have caused." The
economic damage stems from a bizarre irony: even though Mexico bans GM corn
crops on its soil, a third of its imported U.S. corn is transgenic. If
public sentiment turns against GM corn, officials argue that having to
import only non-GM corn would raise prices for consumers.

U.S. corn is the most likely source of the genetic contamination. It arrives
in sacks mixed with unmodified varieties and often ends up at government
stores, where it is sold as food for the poor and their animals. U.S.
biotech firms instruct farmers to keep buffer zones around GM corn to
prevent foreign genes from spreading, but the stores of Oaxaca, where
peasant farmers shop, have no warning signs at all.

Toro's corn grows near a hilltop, above the pueblo of Calpulalpan, with
pine-green mountains in the distance. As she points out which corn stalks
are crosses and which are pure, a strong wind sweeps by--strong enough,
perhaps, to spread pollen to nearby plots. Indeed, Chapela found transgenes
on farms where store-bought corn was never planted. As word of Chapela's
discovery trickled through Oaxaca, villagers were fearful that the
government was going to burn their fields or prosecute farmers. At the
government store in Calpulalpan, the 59-year-old clerk, Elfego Martinez
Perez, claims the corn "can cause a disease called cancer." (That hasn't
kept him from selling it or eating it himself.)

Chapela's detractors, including many scientists, accuse him of exaggerating
the dangers. The term "native corn" is a misnomer, they say, because farmers
have been modifying the genetic makeup of corn through selective breeding
for thousands of years. "We' ve got a lot of utopian idealists worried about
contamination of the old corn varieties with the new. This is completely
idiotic, the way it has been presented," says Norman Bourlag, a Nobel
laureate and founder of the International Wheat and Maize Improvement Center
near Mexico City. Since none of the genes found in the GM corn were active,
the corn didn't exhibit the traits engineered into it. Even if it did, some
critics argue, the GM corn wouldn't necessarily have a selective advantage
because it was engineered to grow well in the United States, not Mexico.
"Just the presence of one new gene is not going to destroy maize in Mexico,"
says David Hoisington, head of the Applied Biotechnology Center at the Wheat
and Maize center. "It's not a threat to biodiversity. It's just one gene
among 50,000 to 60,000 genes." Officials at Monsanto, which holds a patent
on at least one of the genes Chapela found, makes the same argument.
Regardless of which side in the gene wars is correct, one thing is clear:
now that transgenic corn has been let loose in Mexico, stopping its spread
is next to impossible. Bans on the imports of GM corn, as Greenpeace has
called for, would accomplish nothing. And what if all the GM corn in Oaxaca
magically disappeared? Some of the thousands of Mexican migrant workers who
return each year from the United States no doubt carry kernels they reckon
might grow well back on the hillside back home.