Update: The link below was behind a paywall. A new one, via SciDev.net, seems to be open access.
Elena Ãlvarez-Buylla and co-workers have found transgenes from genetically modified maize in landraces in Mexico. Their paper is to be published in Molecular Ecology, but for now we have this news article in Nature.
The evolving story has multiple layers, including the science ethics controversy. Quist and Chapela published the same finding in Nature in 2001, but their methods were questioned, and the journal made an unprecedented statement saying there had been insufficient evidence to justify the publication. Some saw the hand (and money) of Big Biotech in this ((Conflicts around a study of Mexican crops)), and in the subsequent denial of tenure to Chapela at the University of California, Berkeley (that was later overturned). Now Nature reports that the Ãlvarez-Buylla paper was not published in the prestigious Proceedings of the National Academy of Sciences (PNAS) because the journal’s editor-in-chief Randy Schekman, also at Berkeley, considered that “the report could gain undue exposure in the press due to a political or other environmental agenda.”
We’ll see if the current paper settles the scientific controversy. Ortiz-GarcÃa and colleagues did not find any transgenes in a large sample in 2003/4; a result that was found worthy of publication in PNAS. The Nature news article suggests that Ãlvarez-Buylla found the transgenes in only one field (out of more than 100 sampled), and that this field was also sampled by Quist and Chapela. So are we talking about a single farmer with a cousin in Iowa sending seed remittances? Or about a relatively small fraction of maize plants across the country?
It seems entirely obvious that if there are transgenes in U.S. maize, these will spread down to Mexico. Someone needs to find them first, for sure, but the more relevant question is not if transgenes spread, but rather: which, where, what mechanism(s) (long versus short distance dispersal), how fast, how much, how persistent, and what are the consequences, if any? The term “pollution” is used a lot in this debate. Me, I do not believe in pure races.