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Transgenic corn found growing in Mexico

San Diego

Genetically modified corn (maize) has been found growing in Mexico, raising sensitive environmental and cultural issues in the part of the world where the crop was first cultivated centuries ago.

Transgenic corn is widely sold for consumption in Mexico, where more than five million tonnes of corn are imported annually from the United States. But none of the corn is grown commercially there following a 1998 government moratorium.

The disclosure of scattered plots of transgenic corn in the states of Oaxaca and Puebla was made by a government official earlier this month. A research team at the University of California at Berkeley, which is preparing work on the topic for publication, has subsequently accused the official of breaching confidentiality by his disclosure. Preliminary results from a government study appear to confirm the transgenic corn.

Oaxaca, a rural southern state where maize is revered by indigenous people, is the global centre of corn diversity, and the place of origin of strains grown commercially around the world. Environmentalists claim that the arrival of trangenic strains there could disrupt the genome of naturally bred corn.

Reports released in Mexico City last week say that the existence of growing genetically modified corn was discovered by a team led by Ignacio Chapela, a plant molecular biologist from the University of California at Berkeley who has long worked in Oaxaca. A native of Mexico, Chapela confidentially shared preliminary results of his research earlier this year with Mexican government officials. The officials then set up a research team to conduct similar studies.

On 4 September, at a subcommittee meeting of an international food-safety organization, the Codex Alimentarius Commission, Chapela's discovery was revealed publicly by Fernando Ortiz Monasterio, director of Mexico's biosafety commission. Within days, the information had reached the Mexican Congress and the press.

Chapela says he had told Ortiz and other Mexican officials that he was planning to publish his research, and that public disclosure would undermine this. He adds that Ortiz's “breach of confidentiality” will “degrade the quality of information” his team was compiling.

Ortiz denies breaching confidentiality, but acknowledges that he did reveal Chapela's research results in a public forum.

On 17 September, the Mexican environment ministry released partial results of its own study, which revealed that transgenic corn was found in 15 of 22 areas tested in Oaxaca and Puebla.


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Dalton, R. Transgenic corn found growing in Mexico. Nature 413, 337 (2001).

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