europa    seventh

Stakeholder Consultation on the results of the G-TwYST feeding studies

and on general conclusions and recommendations


Written Consultation, 5 -23 Feb 2018

Stakeholder Workshop, 28-29 MARCH 2018, Hotel Seminarie Elzenveld, Lange Gasthuisstraat 25, 2000 Antwerpen, Belgium.



In the course of the European Commission funded research project G-TwYST (Genetically modified plants Two Year Safety Testing) 90-day, 1- and 2-year whole food/feed animal feeding studies were conducted with  GM maize NK603 in order to develop quality criteria and evaluate their scientific value for GMO risk assessment. Planning-stage issues relevant to these feeding studies were discussed in the workshop of December 2014 and in the written consultation of January 2015. The comments received on those two occasions were addressed when finalising the study plans. Comments and G-TwYST-team responses are available at https://www.g-twyst.eu/reports/workshop-documentys-planning-phase.

This consultation will provide an opportunity to review the results obtained and to discuss their interpretation.


The consultation has two subsequent steps.

  1. First, the draft results of the 90-day subchronic toxicity study with diets containing 11% and 33% GM maize NK603 will be made available for a written stakeholder consultation in early February 2018. The deadline for written comments on the results of this study is February 23.
  2. Second step would be a stakeholder workshop, organised on 28-29 March 2018 in Antwerp. This workshop will focus on the draft results of another 90-day study with 50% inclusion rate of GM maize NK603, as well as the one-year and the two-year studies. Also included in the scope would be proposed quality criteria for whole-food animal feeding studies, and preliminary conclusions on the scientific value of such studies for GMO risk assessment. An additional agenda item will be insights from an analysis of scientific controversies around animal feeding studies including the GMO case. Written comments, including interested parties not able to attend, are welcome, and should be submitted before 6 April. Please, note, due to the tight schedule of the final phase of the project, this will be a firm deadline.


The aim of this consultation is to discuss the draft results and preliminary conclusions of the tasks described above.


To prepare for the consultation, documentation will be providedin advance for both the written consultation and the stakeholder meeting to registered parties. An electronic registration form is available here. Deadline for registration is March 14.

Non Disclosure Agreement

Since the documentation will contain data that will be used for publication in peer reviewed journals at a later stage along with draft interpretations and preliminary conclusions, we also require participants in the consultation to sign a Non Disclosure Agreement (NDA). The NDA can be downloaded from the G-TwYST website. Please fill in your name, affiliation, address and signature and send it to or to the address indicated on the NDA form.


Presentation of final results

The final results of G-TwYST will be presented in Bratislava, Slovakia, on April 16, 2018. This event will be open to all who are interested, including press. We will send a seperate invitation in February.

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Final stakeholder consultation open for registration

January 22, 2018

The G-TwYST project includes a stakeholder consultation procedure on the results of the feeding studies and their interpretation in terms of quality criteria and their scientific value for GMO risk assessment. Registration for a written consultation in the course of February 2018 and stakeholder workshop on March 28-29, 2018 in Antwerp is open for registration now. More details about the consultation procedure and registration are available at the G-TwYST website

GRACE publication on Transcriptomics

Scientists form the GRACE consortium evaluated gene expression in rat intestinal tissues based on mandatory 90-day rodent feeding studies with 33% GM maize (MON810) or near-isogenic control maize.


No biological response to the GM-diet was observed in male and in female rat tissues. Transcriptome wide analysis of gene expression by RNA-seq confirmed these findings. Nevertheless, gene ontology (GO) analysis clearly associated a set of distinctly regulated transcripts with circadian rhythms. Differential expression of circadian clock genes was confirmed using RT-qPCR and immunoassays for selected factors, thereby indicating physiological effects caused by the time point of sampling.



Prediction of potential unintended effects of GM-food/feed by transcriptome based profiling of intestinal tissue presents a novel approach to complement classical toxicological testing procedures. Including the detection of alterations in signaling pathways in toxicity testing procedures may enhance the confidence in outcomes of toxicological trials. In this study, no significant GM-related changes in intestinal expression profiles were found in rats fed GM-maize MON810. Relevant alterations of selected cellular pathways (apoptosis, DNA damage and repair, UPR) pointing toward intestinal toxicity of the diets were not observed. Transcriptomic profiles did not reveal perturbations of pathways associated with toxicity, underlining the study results revealed by classical OECD endpoints.



The publication is available at the website of Frontiers in Genetics.