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A subchronic toxicity study was conducted in Wistar rats to evaluate the potential health effects of genetically modified (GM) herbicide-tolerant soybean DAS-68416-4. Rats were fed with diets containing toasted meal produced from GM soybean engineered with aad-12 and pat genes or containing non-GM soybean at a dose of 30.0, 15.0, or 7.5%,w/w% and 0% (control group) for 90 consecutive days. Animals were evaluated for general behavior, body weight gain, food consumption, food use efficiency, etc. At the middle and end of the study, blood and serum samples were collected for routine and biochemical assays. Internal organs were taken for calculating relative weights and doing histopathological examination. The rats were active and healthy without any abnormal symptoms during the entire study period. No biological differences in hematological or biochemical indices were detected. No histopathological changes were observed. Under the conditions of this study, herbicide-tolerant soybean DAS-68416-4 did not cause any treatment-related effects in Wistar rats following 90 days of dietary administration.

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Soybean DAS-8419-2 × DAS-44406-6 was developed to provide protection against certain lepidopteran pests and tolerance to 2,4-dichlorophenoxyacetic acid and other related phenoxy herbicides, and glyphosate- and glufosinate ammonium-containing herbicides. The Genetically Modified Organisms (GMO) Panel previously assessed the two single soybean events and did not identify safety concerns. No new data on the single soybean events, leading to modification of the original conclusions on their safety have been identified. The molecular characterisation, comparative analysis (agronomic, phenotypic and compositional characteristics) and the outcome of the toxicological, allergenicity and nutritional assessment indicate that the combination of the single soybean events and of the newly expressed proteins in the two-event stack soybean does not give rise to food and feed safety and nutritional concerns. In the case of accidental release of viable DAS-8419-2 × DAS-44406-6 seeds into the environment, soybean DAS-8419-2 × DAS-44406-6 would not raise environmental safety concerns. The post-market environmental monitoring plan and reporting intervals are in line with the intended uses of soybean DAS-8419-2 × DAS-44406-6. In conclusion, the GMO Panel considers that soybean DAS-8419-2 × DAS-44406-6, as described in this application, is as safe as its conventional counterpart and the non-genetically modified soybean reference varieties tested with respect to potential effects on human and animal health and the environment.

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DAS-444Ø6-6 soybean was genetically engineered (GE) to withstand applications of three different herbicides. Tolerance to glufosinate and glyphosate is achieved through expression of the phosphinothricin acetyltransferase (PAT) and double-mutated maize 5-enolpyruvyl shikimate-3-phosphate synthase (2mEPSPS) enzymes, respectively. These proteins are expressed in currently commercialized crops and represent no novel risk. Tolerance to 2,4-dichlorophenoxyacetic acid (2,4-D) is achieved through expression of the aryloxyalkanoate dioxygenase 12 (AAD-12) enzyme, which is novel in crops. The safety of the AAD-12 protein and DAS-444Ø6-6 event was assessed for food and feed safety based on the weight of evidence and found to be as safe as non-GE soybean.

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The aryloxyalkanoate dioxygenase-12 (AAD-12) protein is expressed in genetically modified soybean events DAS-68416-4 and DAS-444Ø6-6. Expression of the AAD-12 protein in soybeans confers tolerance to the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) providing an additional herbicide choice to farmers. This enzyme acts by catalyzing the degradation of 2,4-D into herbicidally inactive metabolites. To meet evolving interpretation of regulations in the European Union, three separate 28-day repeat-dose oral mouse studies were conducted at increasing doses of up to 1100 mg AAD-12 protein/kg bw/day. No treatment-related effects were seen in any of these three studies.

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Typically, when a protein is orally toxic, it acts via acute mechanisms, especially at high doses. Therefore, an acute oral toxicity study is considered appropriate for evaluating the safety of transgenic proteins. Soybean plants (events DAS-68416-4 and DAS-444Ø6-6) have been genetically modified to express the aryloxyalkanoate dioxygenase-12 (AAD-12) protein. The AAD-12 protein provides tolerance to the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). This paper summarizes the study designs of two acute oral toxicity studies evaluating the AAD-12 protein and reports the results of these studies. No mortalities or adverse effects were observed in mice when AAD-12 was tested up to a limit dose of 5000 mg/kg body weight. Based on the results of these studies, it can be concluded that AAD-12 protein, as expressed in genetically modified DAS-68416-4 and DAS-444Ø6-6 soybeans, lacks acute toxicity via the oral route.

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Soybean DAS-68416-4 was developed by Agrobacterium tumefaciens-mediated transformation to express the aryloxyalkanoate dioxygenase-12 (AAD-12) protein, conferring tolerance to 2,4-dichlorophenoxyacetic acid (2,4-D) and other related phenoxy herbicides, and the phosphinothricin acetyltransferase (PAT) protein, conferring tolerance to glufosinate ammonium-based herbicides. The molecular characterisation data and bioinformatics analyses did not identify issues requiring further assessment for food/feed safety. The agronomic and phenotypic characteristics tested revealed no relevant differences between soybean DAS-68416-4 and its conventional counterpart, except for 'days to 50% flowering'. The compositional analysis identified no differences requiring further assessment, except for an increase (up to 36%) in lectin activity in soybean DAS-68416-4. Such increase is unlikely to raise additional concerns for food/feed safety and nutrition for soybean DAS-68416-4 as compared to its conventional counterpart and the non-GM reference varieties. There were no concerns regarding the potential toxicity and allergenicity of the two newly expressed proteins, and no evidence that the genetic modification might significantly change the overall allergenicity of soybean DAS-68416-4. Soybean DAS-68416-4 is as nutritious as its conventional counterpart and the non-GM reference varieties. There are no indications of an increased likelihood of establishment and spread of occasional feral soybean DAS-68416-4 plants, unless these are exposed to the intended herbicides. The likelihood of environmental effects resulting from the accidental release of viable seeds from soybean DAS-68416-4 into the environment is therefore very low. The post-market environmental monitoring plan and reporting intervals are in line with the intended uses of soybean DAS-68416-4. The GMO Panel concludes that the information available addresses the scientific comments of the Member States and that soybean DAS-68416-4, as described in this application, is as safe as its conventional counterpart and the tested non-GM reference varieties with respect to potential effects on human and animal health and the environment in the context of the scope of this application.

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Soybean DAS-44406-6 expresses 5-enolpyruvyl-shikimate-3-phosphate synthase (2mEPSPS), conferring tolerance to glyphosate-based herbicides, aryloxyalkanoate dioxygenase (AAD-12), conferring tolerance to 2,4-dichlorophenoxyacetic acid (2,4-D) and other related phenoxy herbicides, and phosphinothricin acetyl transferase (PAT), conferring tolerance to glufosinate ammonium-based herbicides. The molecular characterisation data and bioinformatics analyses did not identify issues requiring assessment for food/feed safety. The agronomic and phenotypic characteristics revealed no relevant differences between soybean DAS-44406-6 and its conventional counterpart, except for pod count, seed count and yield. The compositional analysis identified no differences requiring further assessment, except for an increase (up to 31%) in lectin activity in soybean DAS-44406-6. Such increase is unlikely to raise additional concerns for food/feed safety and nutrition of soybean DAS-44406-6 as compared to its conventional counterpart and non-GM reference varieties. There were no concerns regarding the potential toxicity and allergenicity of the three newly expressed proteins, and no evidence that the genetic modification might significantly change the overall allergenicity of soybean DAS-44406-6. Soybean DAS-44406-6 is as nutritious as its conventional counterpart and the non-GM soybean reference varieties tested. There are no indications of an increased likelihood of establishment and spread of occasional feral soybean DAS-44406-6 plants, unless exposed to the intended herbicides. The likelihood of environmental effects from the accidental release of viable seeds from soybean DAS-44406-6 into the environment is therefore very low. The post-market environmental monitoring plan and reporting intervals are in line with the intended uses of soybean DAS-44406-6. In conclusion, the GMO Panel considers that the information available for soybean DAS-44406-6 addresses the scientific comments raised by Member States and that soybean DAS-44406-6, as described in this application, is as safe as its conventional counterpart and non-GM soybean reference varieties with respect to potential effects on human and animal health and the environment in the context of the scope of this application.

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Background Osmolytes with their effective stabilizing properties are accumulated as protectants not only against salinity but also against denaturing harsh environmental stresses such as freezing, drying, high temperatures, oxygen radicals and radiation. The present work seeks to understand how Halomonas sp. AAD12 cells redirect carbon flux specifically to replenish reactions for biomass and osmolyte synthesis under changing salinity and temperature. To accomplish this goal, a combined FBA-PCA approach has been utilized. Results Experimental data were collected to supply model constraints for FBA and for the verification of the model predictions, which were satisfactory. With restrictions on the various combinations of selected anaplerotic paths (reactions catalyzed by phosphoenolpyruvate carboxylase, pyruvate carboxylase or glyoxylate shunt), two major phenotypes were found. Moreover, under high salt concentrations, when the glucose uptake rate was over 1.1 mmoL DCW- 1 h- 1, an overflow metabolism that led to the synthesis of ethanol caused a slight change in both phenotypes. Conclusions The operation of the glyoxylate shunt as the major anaplerotic pathway and the degradation of 6-phosphogluconate through the Entner-Doudoroff Pathway were the major factors in causing a distinction between the observed phenotypes.

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