Last year, a French researcher made waves by announcing a study that suggested genetically modified corn could lead to an increased incidence of tumors in lab animals. But the way the finding was announced seemed designed to generate publicity while avoiding any scientific evaluation of the results. Since then, the scientific criticisms have rolled in, and they have been scathing. Now, the editor of the journal that published it has decided to pull the paper despite the objections of its primary author.

The initial publication focused on corn that had been genetically engineered to carry a gene that allowed it to break down a herbicide. French researchers, led by Gilles-Eric Séralini, fed the corn, with and without herbicide, to rats. Control populations were given the herbicide alone or unmodified corn. The authors concluded that the genetically modified corn led to an elevated incidence of tumors and early death.

But even a cursory glance at the results suggested there were some severe problems with this conclusion. To begin with, there were similar effects caused by both the genetically engineered crop and by the herbicide it was designed to degrade. None of the treatments showed a dose effect; in some cases, the lowest doses had the most dramatic effect. And, if the treatment populations were combined, in some cases they were healthier than the controls. Tests of whether the results were statistically significant were completely lacking.

And, since then, the scientific response has been withering. The German and EU food regulators looked the results over, but found them inadequate. The paper itself has accumulated a host of Letters to the Editor attached to it. And a different journal published an entire paper devoted to outlining its deficiencies.

All of these criticisms of the study could have been incorporated into the original press coverage, except for the fact that the people behind the study manipulated journalists to ensure that they were unable to obtain any outside evaluations of the paper. Nevertheless, even as the criticisms rolled in, the researchers remained defiant, and anti-GMO activists continued to promote the paper as evidence of the dangers posed by genetically modified crops.

Now, the editor of Food and Chemical Toxicology, the journal in which this study was published, has decided its flaws are so severe that including multiple Letters to the Editor with the study just won't cut it. In response to the initial complaints, he had set up a panel that looked over the paper and the additional data provided by Séralini. According to one letter from the editor, obtained by an anti-GMO activist group, "The panel had many concerns about the quality of the data and ultimately recommended that the article should be withdrawn." The editor has agreed with this recommendation and has already written a statement that will replace it.

Séralini has been asked to get in touch to discuss the details of the paper's withdrawal, but he has announced that he stands by his conclusions. This will ultimately force the editor to withdraw it over Séralini's objections.

This sort of retraction is a bit unusual. In one heavily publicized past example, a research group described bacteria that could supposedly replace phosphate with arsenate. Despite a large number of problems with that paper (including a failure to reproduce the original results), Science still hasn't pulled it. In contrast, a paper linking Chronic Fatigue Syndrome to a virus has been pulled, perhaps because there were more serious questions about the scientific procedures used to generate its results.

For the GMO paper, the situation is complex. According to the publisher, Elsevier, there is no evidence of any fraud or data manipulation. However, the number of animals used was insufficient to support any conclusions, and the paper certainly drew some. This goes against the journal's guidelines, and thus they seem to be admitting the paper should never have been published in the first place. That would seem to be a failure of editorial process and peer review, yet Elsevier states, "The peer review process is not perfect, but it does work."

(An additional problem that could justify retraction, noted by one of the papers linked above, is that animal welfare rules call for animals that develop tumors to be euthanized, while Séralini let the tumors grow to horrific sizes.)

If the precise grounds for retraction aren't entirely clear, the response of the groups campaigning against genetically modified foods is. A statement released by the group GMWatch basically says that the paper was fine, the editor is being unethical, and Monsanto might be behind it all. So, it seems that Séralini's paper will continue to be brought up long after it's removed from the formal scientific literature.