Safety evaluation of DAS-44406-6 soybeans in Wistar rats

Subchronic feeding study of glyphosate-tolerant maize GG2 with the gr79-epsps and gat genes in Wistar Han RCC rats

The genetically modified (GM) maize GG2 contains gr79-epsps and gat genes, conferring glyphosate tolerance. The present study aimed to investigate potential effects of maize GG2 in a 90-day subchronic feeding study on Wistar Han RCC rats. Maize grains from GG2 or non-GM maize were incorporated into diets at concentrations of 25% and 50% and administered to Wistar Han RCC rats (n = 10/sex/group) for 90 days. The basal-diet group of rats (n = 10/sex/group) were fed with common commercialized rodent diet. Compared with rats fed with the corresponding non-GM maize and the basal-diet, no biologically relevant differences were observed in rats fed with the maize GG2, according to the results of body weight/gain, feed consumption/utilization, clinical signs, mortality, ophthalmology, clinical pathology (hematology, prothrombin time, urinalysis, serum chemistry), organ weights, and gross and microscopic pathology. Under the conditions of this study, these results indicated that maize GG2 is as safe as the non-GM maize in this 90-day feeding study.

Subchronic toxicity study in rats evaluating herbicide-tolerant soybean DAS-68416-4

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.

DP-2Ø2216-6 maize does not adversely affect rats in a 90-day feeding study

Maize plants containing event DP-2Ø2216-6 (DP202216), which confers herbicide tolerance through expression of phosphinothricin acetyltransferase and enhanced grain yield potential via temporal modulation of the native ZMM28 protein, were developed for commercialization. To address current regulatory expectations, a mandatory 90-day rodent feeding study was conducted to support the safety assessment. Diets containing 50% by weight of ground maize grain from DP202216, non-transgenic control, and 3 non-transgenic reference varieties, were fully characterized, along with the grain, and diets were fed to Crl:CD®(SD) rats for at least 90 days. As anticipated, no biologically-relevant effects or toxicologically-significant differences were observed on survival, body weight/gain, food consumption/efficiency, clinical and neurobehavioral evaluations, ophthalmology, clinical pathology (hematology, coagulation, clinical chemistry, urinalysis), organ weights, or gross and microscopic pathology parameters in rats fed a diet containing up to 50% DP202216 maize grain when compared with rats fed diets containing control or reference maize grains. The results of this study support the conclusion that maize grain from plants containing event DP-2Ø2216-6 is as safe and nutritious as maize grain not containing the event and add to the significant existing database of rodent subchronic studies demonstrating the absence of hazards from consumption of edible fractions of genetically modified plants.

Subchronic feeding toxicity studies of drought-tolerant transgenic wheat MGX11-10 in Wistar Han RCC rats

A subchronic toxicity study were conducted in Wistar Han RCC rats to evaluate the potential health effects of genetically modified (GM), drought-tolerant wheat MGX11-10. Rats were fed a rodent diet formulated with MGX11-10 and were compared with rats fed a diet formulated with its corresponding non-transgenic control Jimai22 and rats fed a basal diet. MGX11-10 and Jimai22 were ground into flour and formulated into diets at concentrations of 16.25, 32.5, or 65%, w/w% and fed to rats (10/sex/group) for 13 weeks. Compared with rats fed Jimai22 and the basal-diet group, no biologically relevant differences were observed in rats fed the GM diet with respect to body weight/gain, food consumption/efficiency, clinical signs, mortality, ophthalmology, clinical pathology (hematology, prothrombin time, urinalysis, clinical chemistry), organ weights, and gross and microscopic pathology. Under the conditions of this study, the MGX11-10 diets did not cause any treatment-related effects in rats following at least 90 days of dietary administration as compared with rats fed diets with the corresponding non-transgenic control diet and the basal-diet group. The MGX11-10 diets are considered equivalent to the diets prepared from conventional comparators. The results demonstrated that MGX11-10 wheat is as safe and wholesome as the corresponding non-transgenic control wheat.