The journal Food and Chemical Toxicology has announced the retraction of a controversial study purportedly linking genetically modified organisms (GMOs) to mammary tumors in rats. Led by University of Caen Molecular Biology Professor Gilles-Éric Séralin, the November 2012 study garneredpublic attention for reporting that female rats fed GM maize developed more mammary tumors than a control group raised on conventional feed. After further review, however, the journal’s editor-in-chief concluded that “both the low number of animals in each study group and the particular strain selected” were cause for concern.

“A more in-depth look at the raw data revealed that no definitive conclusions can be reached with this small sample size regarding the role of either NK603 or glyphosate in regards to overall mortality or tumor incidence,” notes thejournal’s retraction statement. “Given the known high incidence of tumors in the Sprague-Dawley rat, normal variability cannot be excluded as the cause of the higher mortality and incidence observed in the treated groups.” See, November 28, 2013.