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Q:
What does GMOAnwers have to say about the fact that results from scientist lab research has shown cancers and sterility in rats in only three generations of breeding, while being fed GMO food as their main diet. Also why is it that the scientist who have done this research have been discredited and ostracized for their findings.
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A:Expert Answer

First, your question appears to refer to one or more studies that have been retracted from, or never formally published in, a peer-reviewed scientific journal. If you are unfamiliar, retraction is the process by which scientific papers are officially withdrawn from the public record. According to Retraction Guidelines published by the Committee on Publication Ethics:

 

“Journal editors should consider retracting a publication if:

  • they have clear evidence that the findings are unreliable, either as a result of misconduct (e.g., data fabrication) or honest error (e.g. miscalculation or experimental error)
  • the findings have previously been published elsewhere without proper cross referencing, permission or justification (i.e. cases of redundant publication)
  • it constitutes plagiarism
  • it reports unethical research” (Wager et al., 2009)


Clearly, a paper associated with any of the issues listed above would raise serious questions about the research and conclusions originally reported. Consequently, the scientific community does not rely on the conclusions of retracted papers as the basis for further scientific study.

 

If you are referencing Gilles-Eric Séralini’s two-year rat-feeding study, GMO Answers has received several related questions. Alan McHughen, CE biotechnology specialist and geneticist, provided a detailed response about the study. Here is an excerpt:

 

“The pictures from that study conducted by Gilles-Eric Séralini are frightening—and made for sensationalistic media coverage. However, when teams of scientists from around the world looked at the study carefully, they found that the conclusions drawn by Séralini were not credible, that the study itself was seriously flawed and provided no new grounds for concern about GM food. 

 

“The paper was criticized by public scientific and medical societies worldwide for its faulty experimental design, statistical analysis and interpretation and presentation of results. Problems included the well-known fact that the strain of rats used in the study (Sprague-Dawley) are prone to develop tumors at around age two, regardless of their diet; Séralini attributed the tumors to the GM corn rations, but he could as easily have shown pictures of rats fed no GM corn but still full of tumors. Séralini’s data analysis was also unusual; the German risk-assessment agency found it ‘impossible to comprehend…’”

 

You can read McHughen’s full response here: http://gmoanswers.com/ask/have-you-reviewed-study-showing-gmos-caused-cancer-lab-rats.

 

The Séralini study was retracted in November 2013 by Elsevier’s Food and Chemical Toxicology, the journal that originally published it. An excerpt from the statement reads:

“The journal Food and Chemical Toxicology retracts the article ‘Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize,’ which was published in this journal in November 2012. This retraction comes after a thorough and time-consuming analysis of the published article and the data it reports, along with an investigation into the peer review behind the article…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. 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.”

 

This statement makes reference to the issue of the scientists’ use of Sprague-Dawley rats. Hopefully, this issue was clarified in a previous answer on this site (http://gmoanswers.com/ask/if-critics-claim-seralinis-well-known-study-flawed-having-used-sprague-dawley-rat-doesnt-make).

 

You’ve also mentioned studies that claim adverse effects on reproductive health. We presume you may be referring to a research report released by the Austrian Federal Ministry of Health, Family and Youth in November 2008. The authors originally reported negative effects on reproduction in mice; however, national risk-assessment experts at the European Food Safety Authority (EFSA) reviewed the report and concluded there were several serious deficiencies in the study design and no conclusions could be made (http://www.efsa.europa.eu/en/events/event/gmo081203-m.pdf).

 

Similarly, national risk-assessment experts at Food Standards Australia New Zealand (FSANZ) had a negative opinion of the Austrian study:

 

“The conclusions drawn by Velimirov et al. concerning a reproductive effect in mice fed a diet containing GM corn are not supported by the evidence presented in this report. Not only can significant flaws in the experimental design be identified, but there is also a general lack of detail and transparency in the presentation of information on methodology and the statistical evaluation of data. These deficiencies appear to have contributed to erroneous interpretations of the results” (FSANZ, 2008).

 

Ultimately, the Austrian research group did not provide additional data or a suitable statistical analysis to address the concerns raised by EFSA and FSANZ, and the report was withdrawn in 2010.

 

For the reasons outlined above, there has been no evidence or scientific basis for cancer, reproductive or other health concerns raised by these flawed studies.

 

A:Expert Answer

If you are referencing Gilles-Eric Séralini’s two-year rat-feeding study, GMO Answers has received several related questions. Alan McHughen, CE biotechnology specialist and geneticist, provided a detailed response about the study. Here is an excerpt:

 

“The pictures from that study conducted by Gilles-Eric Séralini are frightening—and made for sensationalistic media coverage. However, when teams of scientists from around the world looked at the study carefully, they found that the conclusions drawn by Séralini were not credible, that the study itself was seriously flawed and provided no new grounds for concern about GM food. 

 

“The paper was criticized by public scientific and medical societies worldwide for its faulty experimental design, statistical analysis and interpretation and presentation of results. Problems included the well-known fact that the strain of rats used in the study (Sprague-Dawley) are prone to develop tumors at around age two, regardless of their diet; Séralini attributed the tumors to the GM corn rations, but he could as easily have shown pictures of rats fed no GM corn but still full of tumors. Séralini’s data analysis was also unusual; the German risk-assessment agency found it ‘impossible to comprehend…’”

 

You can read McHughen’s full response here: http://gmoanswers.com/ask/have-you-reviewed-study-showing-gmos-caused-cancer-lab-rats.

 

The Séralini study was recently retracted by Elsevier’s Food and Chemical Toxicology, the journal that originally published it. An excerpt from the statement reads:

 

“The journal Food and Chemical Toxicology retracts the article ‘Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize,’ which was published in this journal in November 2012. This retraction comes after a thorough and time-consuming analysis of the published article and the data it reports, along with an investigation into the peer review behind the article…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. 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.”

 

If you have any additional questions, please ask at http://www.gmoanswers.com/ask.

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