Absolute quantitative detection of genetically modified soybean MON87708×MON89788 with stacked traits by digital polymerase chain reaction

The main advantage of digital PCR(dPCR) is that it facilitates absolute quantification of the target without reference to the standard/calibration curve.Crystal droplet dPCR has a three-color staining detection function,which enables multiplex PCR reaction.In this study,this technique was used to establish triple dPCR detection for the genetically modified soybean MON87708 × MON89788 with stacked traits.Specific absolute quantitative detection was accomplished for the genomic DNA extracted from the homogenized seeds of GM stack MON87708× MON89788 soybean.Our results can serve as a reference for the absolute quantitative detection of stacked events of genetically modified crops.

Evaluation of Uncertainty in Measuring the Content of CaM V35S Promoter in Genetically Modified Soybean,GTS40-3-2,by Real-time Quantitative PCR

[ Objective ] This study aimed to investigate the major contributors to the measurement uncertainty in quantitative analysis of genetically modified ingreclients and improve the quality of quantitative detection of genetically modified components. [ Method] The content of CaMV35S promoter （parameter） in GTS40- 3-2 soybean powder samples was measured to estimate the measurement uncertainty preliminarily. [ Result] Type A uncertainty （uA） ＇ type B uncertainty （uB） and combined standard uncertainty （Uc） were 0.0 004, 0.002 and 0.002, respectively. At a confidence level ofp = 95% and freedom degree of Voff = 3 251, coverage factor k = 1.96, expanded uncertainty U = 0.004. The final measurement result was C = 0.028 ± 0. 004, which was dose to the conventional true value （0.03）. Thus, the measurement uncertainty was relatively small, indicating a high quality of measurement. In this study, uncertainty evaluation indicated that the deviation of micro liquid transfer made the greatest contribution to the measurement uncertainty. [ Cludusion ] The deviation of micro liquid transfer should be reduced to im- prove the quality of measurement.

Genetically Modified Doubts Imported GM soybeans impact China’s local farmers and create food safety concerns

The cooking oil made from the imported soybeans does not contain transgenic proteins. So there will be no food safety threat.

Effects of Severe Drought and Glyphosate Stress on Physiological Characteristics and Protein Expression of Photosystem Ⅱ in Genentically Modified Soybean

[Objective] The paper was to investigate effects of glyphosate stress on physiological characteristics and protein expression of photosystem Ⅱ(PSⅡ) in genentically modified soybean GTS 40-3-2 seedlings under severe drought condition. [Method] A pot experiment was carried out in growth chamber to determine the response of genetically modified soybean treated by severe drought stress and different concentrations of glyphosate at the third compound leaf stage. [Result] Severe drought treatment increased the electrolyte leakage(EL), superoxide dismutase(SOD) and peroxidase(POD) activities, and decreased the relative water content(RWC), chlorophyll content, and catalase(CAT) activity. The EL, SOD and POD activities were significantly increased in severe drought and glyphosate treatments, which were related to glyphosate concentrations. The chlorophyll content decreased, which was also related to glyphosate concentrations. But the BWC and CAT activity were not affected by glyphosate concentrations. Western blot displayed that PSⅡ protein Lhcb2 was not affected by stress conditions and stably expressed. D1, D2 and Lhcb4 protein level decreased, and there was no significant change in Lhcb1 expression under severe drought stress. The protein levels of D1, D2, Lhcb1 and Lhcb4 decreased with the increase of glyphosate concentrations under severe drought and glyphosate stress. When the glyphosate concentrations were 0.92 and 1.84 kg·ai/hm^2, the protein levels of D1, D2 and Lhcb4 were slightly higher than those in severe drought stress. When the glyphosate concentrations were 3.68 and 7.36 kg·ai/hm^2, the protein level of D1, D2, Lhcb1 and Lhcb4 decreased sharply. [Conclusion] This research provides a theoretical basis for production of genetically modified soybean.

Construction of the Plasmid Reference Molecule for Detection of Transgenic Soybean MON89788

[Objective] The aim was to construct a plasmid reference molecule (PRM) for detection of transgenic soybean MON89788. [Method] the lectin gene sequence,3'-junction and 5'-junction sequence between host plant DNA integrated DNA of MON89788 soybean were amplified independently,and the three fragments were cloned into the cloning vector pMD18-T in order through molecular manipulation method to construct pMD-LM3M5,the applicability of the constructed novel PRM was tested. [Result] Sequencing confirmation result showed that the PRM was 3 700 bp in length,containing 1 029 bp of recombined DNA fragment. The limits of qualitative detection of the PRM were 10 copies. [Conclusion] The PRM constructed in this study was suitable for the identification of MON89788 event.

A Novel Approach for Evaluation of Food Functions and Safety Applied in RR GM Soybeans

[Objective] This study aimed to evaluate tbe healthy risk of genetically modified （ GM ） soybeans by using a novel approach for functions and safety of food. [ Me^od] Different from traditional evaluation of substantial equivalence, three great innovations were performed in this study, involving in basic diet, evalu- ation approaches and principle, as well as the clarification of connotation differences between absolute and relative mass of organs. Hence a novel BDI-GS （Bendib Damage Index and General Score） evaluation approach was established and applied in comparative evaluation between RR GM and natural soybeans. Healthy male ICR mice during linear growth were selected; experimental mice were fed with 15% RR GM soybeans and 15% natural soybeans blending maize meal diets, and control mice were fed with single maize meal diet for 13 d; the mice were dissected after collecting blood samples and perfectly obtained nine organs or tissues to re- cord their masses and conduct statistical analyses. [Result] Plenty of matching information was obtained through simple design. The growth performance of treated mice was markedly of individual differences, some mice were thwarted due to regular intake of RR soybeans. Meanwhile, the functions and safety of RR soybeans were markedly lowered in overall nutritional and healthy effects than those of natural soybeans expressed in GS values, and presents some declines in nutrition and health of thymus, pancreas and spermary; especially, it can make thymus immune （P 〈0.05） in markedly lower level than that of natural soybeans. [ Conclusion] Therefore, major troubles and risks of RR soybeans intake are of personal risks in different degrees, in addition, it may increase sub-health and related chronic epi- demics risks, and herein it will presents certain safety issues. The creation of this novel evaluation system provides a simple and available evaluation approach for functions and potential risks revelation of food effects, and will yield far-reaching influences to safety evaluation and healthy development of GM foods, as well as public health.

A Broad Spectrum Identification Approach for Two Generations of epsps GM Soybeans

In order to accurately identify the first and second generations of epsps genetically modified(GM) soybeans and related products,a broad spectrum identification approach was established using the real time Polymerase Chain Reaction(PCR) principle according to the homology of epsps genes of the first and second generations of GM soybeans.A pair of primer and probe was designed to simultaneously identify exogenous gene epsps of two generations of GM soybeans.Besides,evaluation was carried out on this approach from the accuracy,specificity,sensitivity and reproducibility.The experimental results indicated that(ⅰ) although there is certain difference in epsps gene sequence between the first and second generations of epsps genetically modified(GM) soybeans,the established approach can simultaneously detect the epsps genes of the bean curd using two generations of soybean as raw materials;(ⅱ) in the accuracy and specificity experiment,only cp4-epsps genes of two generations of GM soybeans were detected,so this approach has high specificity and accuracy;(ⅲ) in the experiment of 5 copies of epsps genes of 40 repeated identification reaction systems,5 copies of epsps genes can be detected each time,therefore at 100% confidence level,this approach can identify 5 copies of epsps genes,showing that this approach has high sensitivity and reproducibility.