By Sophie Harrington
In November 2012, researchers from France shocked the world when they published a highly controversial paper claiming that there was a link between genetically modified foods and the incidence of cancer. The work by Dr Gilles-Eric Séralini and his team from the University of Caen, France showed that feeding rats Roundup-resistant maize was leading to the growth of tumours in lab rats. However, after a year of heated debate and outcry in the scientific community following the publication of the study, on 20 November the paper was retracted by Food and Chemical Toxicology, the journal which had originally published it.
Shortly after its publication, concerns were raised over the quality of the data used in the paper, outlined in various letters to the editor of the journal. These included the small sample size of each test group, inconsistent interpretation of results, and apparently contradictory results that were not addressed by the authors.
Additionally, the strain of rats Dr Séralini chose to use is known to have a higher incidence of cancer, particularly in old age. The study considered the development of cancer over two years in rats, which is near the end of the rats’ natural lifespan. It has been suggested that the high incidence of cancer the study reported was due to the strain’s propensity to develop cancer late in life, rather than due to their exposure to GMOs.
The decision to retract the paper is controversial in itself. Questions have been raised regarding the decision to retract a paper without evidence of fraud or misrepresentation of data. It appears that the decision to retract was taken with the view that the paper should never have been published in the first place. In a letter announcing the proposed retraction, William J. Hayes, the editor-in-chief of Food and Chemical Toxicology, stated that the results are inconclusive, and consequently “do not reach the threshold for publication.”
Unsurprisingly, Dr Séralini has condemned the decision to retract. Since its publication, the paper had been cited 28 times, and Dr. Séralini has been called to testify before the French National Assembly on the paper. Critics of the decision have called out the ostensible conflict of interest seen in the recent appointment of an ex-Monsanto employee to the post of associate editor at Food and Chemical Toxicology; Monsanto is currently the world-leader for the production of GMO foods, and it also produced the GM strain of maize used in the study.
The retraction of this paper has been seen by many as a victory for many in the scientific community who support the safety of GMOs. It remains to be seen, however, whether backlash by those concerned with the reasoning behind the retraction will increase the controversy over genetically modified organisms.
For more information, see Retraction Watch’s coverage of the event: http://retractionwatch.com/2013/11/28/controversial-seralini-gmo-rats-paper-to-be-retracted/
Details of the retraction letter and further discussion of the paper can be found here: http://www.sciencedirect.com/science/article/pii/S0278691512005637