Import of glyphosate resistent oilseed rape 73496

Advisory reports | 08.02.2013 | CGM/130208-02

This opinion concerns an application for import and processing of genetically modified oilseed rape 73496. Genetically modified oilseed rape 73496 produces the GAT4621 N-acetyltransferase protein which detoxifies glyphosate by acetylation, leading to N-acetyl glyphosate as a residue. As a result, 73496 is resistant to glyphosate containing herbicides. Due to the insertion of the gat4621 gene cassette a tpt gene located in the 5’ border region of the insert was disrupted.
COGEM points out that the molecular characterisation of 73496 is incomplete because the insert site was not completely characterised.
The establishment of small populations of 73496 oilseed rape on locations where glyphosate is frequently applied to control weeds, e.g. on railway tracks, cannot be excluded. If small 73496 oilseed rape populations become established, cross-fertilisation could occur with oilseed rape and/or wild relatives, in particular turnip. The resulting progeny will not be different from progeny formed after cross-fertilisation with conventional oilseed rape varieties apart from the ability to produce the GAT4621 N-acetyltransferase protein and the disruption of a tpt gene. COGEM considers it unlikely that any resulting progeny will possess a selective advantage unless glyphosate is applied.
COGEM recommends to include the monitoring of distribution routes for the occurrence of oilseed rape volunteers in the monitoring plan. It cannot be excluded that cross-fertilisation could lead to the eventual stacking of transgenes in a single oilseed rape plant. COGEM is of the opinion that stacking of the traits in the present oilseed rape varieties will not lead to an environmental risk because these traits are unlikely to lead to an increased fitness or a selective advantage under natural conditions. However, it is important to know whether stacking occurs in order to allow future risk assessments to take into account the presence of established GM oilseed rape with stacked traits. A stacked event would most likely occur in a location where herbicides are frequently used, such as railway tracks. Therefore, COGEM advises to involve railway companies and/or companies in charge of the maintenance of railway tracks in the post-market monitoring plan in order to monitor the occurrence of GM oilseed rape on railway tracks.
In summary, COGEM is of the opinion that the molecular characterisation of 73496 is incomplete. Moreover, COGEM is of the opinion that the monitoring plan of 73496 should be improved before a market authorisation is granted. Therefore, COGEM cannot advise positively on the application for import and processing of 73496 oilseed rape. Due to time constraints, COGEM did not assess all elements of the application (e.g. putative effects of N-acetyltransferase on other compounds). Therefore, COGEM reserves its right to comment further on this application in the future.

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