James Meek, science correspondent
Guardian

Saturday June 8, 2002

Britain's most prestigious science journal, Nature, ignored the advice of most of its own advisers when it took the unprecedented step of retracting an article claiming that DNA from genetically modified maize had leached into native, wild maize in Mexico, BBC2's Newsnight claimed last night.

It reported that two of the three independent experts consulted by the journal after strong pressure from sections of the scientific-business community had endorsed the key conclusions of the paper.

The retraction by Nature's editor, Philip Campbell, of a paper which had already been peer-reviewed by scientists and published was unprecedented in the journal's 133-year history. He said his action had been based on critiques from three, unnamed, independent scientists.

Newsnight said it had obtained copies of the comments from the three. Only one disputed the key findings of the paper - that DNA from GM plants had turned up in wild maize, even though GM maize is illegal in Mexico. Only this expert had said the paper should be disowned.

All agreed that another finding in the paper, that the transferred DNA would be passed to successive generations of wild maize, genetically contaminating wild plants in perpetuity, was flawed.

Asked why he had not made the experts' views clear in his Nature statement, Mr Campbell said: "Our standard procedure is to make our own judgments. We wanted to make clear there were problems with the evidence based on our judgment based on the advice of independent referees."

One of the authors of the original paper was Dr Ignacio Chapela, a Mexican scientist based at the University of California, Berkeley. Confirmation of his findings came last month, not long after the Nature disavowal, when Jorge Soberon, executive secretary of Mexico's national commission on biodiversity, told a conference at the Hague that tests showed that contamination of wild crops by rogue DNA was far worse than first reported.

It is thought that the contamination occurred as the result of pollination of wild maize by crops grown illegally by Mexican peasants from imported GM maize feed.