Maize Event MON810 Research Articles

Collaborative Ring Trial of the Applicability of a Reference Plasmid DNA Calibrant in the Quantitative Analysis of GM Maize Event MON810.

Certified reference materials (CRMs) is one of the critical requirements in a quantitative analytical method, such as in the quantification of genetically modified (GM) contents in food/feed products. Plasmid-DNA-based CRMs are becoming essential in GM content quantification. Herein, we report the construction of one plasmid DNA calibrant, pMON810, for the quantification of the GM maize event MON810 which is commercially planted and used for food/feeds worldwide, and the collaborative ring trial was used to validate its applicability. pMON10 was proven to have high specificity for the MON810 event. The limit of detection (LOD) and limit of quantification (LOQ) of real-time PCR assays of MON810 event and maize endogenous gene using pMON810 as calibrant was 2 copies/μL and 5 copies/μL, respectively. A total of eight laboratories participated in the ring trial and returned valid test results. Each sample was performed with three repeats and three parallels in each repeat. Statistical analysis of the ring trial results showed that pMON810 as a calibrant had high PCR efficiency (ranging from 0.885 to 1.008) and good linearity (ranging from 0.9933 to 0.9997) in MON810 and endogenous gene real-time PCR assays. The bias between the test values and true values ranged from 4.60 to 20.00% in the quantification of five blind samples. These results indicate that pMON810 is suitable for use as a calibrant for the quantification of MON810 events in routine lab analysis or to evaluate detection methods for MON810, as well as being used as a substitute for the matrix-based CRM of MON810.

Performance of Bt maize event MON810 in controlling maize stem borers Chilo partellus and Busseola fusca in Uganda

Stem borers are major insect pests of maize in Uganda. A study was conducted in 2014–2016 to assess the performance of Bt hybrids expressing Cry1Ab (event MON810) against the two major stem borer species in Uganda – the African stem borer (Busseola fusca) and the spotted stem borer (Chilo partellus) – under artificial infestation. The study comprised 14 non-commercialized hybrids, including seven pairs of Bt and non-Bt hybrids (isolines), three non-Bt commercial hybrids and a conventional stem borer resistant check. All stem borer damage parameters (leaf damage, number of internodes tunneled and tunnel length) were generally significantly lower in Bt hybrids than in their isolines, the conventionally resistant hybrid, and local commercial hybrids. Mean yields were significantly higher by 29.4–80.5% in the Bt hybrids than in the other three categories of non-Bt hybrids. This study demonstrated that Bt maize expressing Cry1Ab protects against leaf damage and can limit entry of stem borers into the stems of maize plants, resulting in higher yield than in the non-transgenic hybrids. Thus, Bt maize has potential to contribute to the overall management package of stem borers in Uganda.

Humoral and cellular immune response in Wistar Han RCC rats fed two genetically modified maize MON810 varieties for 90\xa0days (EU 7th Framework Programme project GRACE)

The genetically modified maize event MON810 expresses a Bacillus thuringiensis-derived gene, which encodes the insecticidal protein Cry1Ab to control some lepidopteran insect pests such as the European corn borer. It has been claimed that the immune system may be affected following the oral/intragastric administration of the MON810 maize in various different animal species. In the frame of the EU-funded project GRACE, two 90-day feeding trials, the so-called studies D and E, were performed to analyze the humoral and cellular immune responses of male and female Wistar Han RCC rats fed the MON810 maize. A MON810 maize variety of Monsanto was used in the study D and a MON810 maize variety of Pioneer Hi-Bred was used in the study E. The total as well as the maize protein- and Cry1Ab-serum-specific IgG, IgM, IgA and IgE levels, the proliferative activity of the lymphocytes, the phagocytic activity of the granulocytes and monocytes, the respiratory burst of the phagocytes, a phenotypic analysis of spleen, thymus and lymph node cells as well as the in vitro production of cytokines by spleen cells were analyzed. No specific Cry1Ab immune response was observed in MON810 rats, and anti-maize protein antibody responses were similar in MON810 and control rats. Single parameters were sporadically altered in rats fed the MON810 maize when compared to control rats, but these alterations are considered to be of no immunotoxicological significance.

Annual post-market environmental monitoring report on the cultivation of genetically modified maize MON810 in 2016.

Following a request from the European Commission, EFSA assessed the annual post‐market environmental monitoring (PMEM) report for the 2016 growing season of the Cry1Ab‐expressing maize event MON 810 provided by Monsanto Europe S.A. Partial compliance with refuge requirements was reported in Spain, as observed in previous years. EFSA reiterates the need to achieve full compliance in areas of high maize MON 810 adoption to delay resistance evolution, and therefore advocates increasing the level of compliance in such areas. Resistance monitoring data do not indicate a decrease in susceptibility to the Cry1Ab protein in the field corn borer populations tested in the 2016 season. However, EFSA identified some methodological and reporting limitations pertaining to resistance monitoring that need improvement in future PMEM reports. No complaints related to corn borer infestation of maize MON 810 were received via the farmer alert system during the 2016 cultivation season. EFSA encourages the consent holder to provide more information on this complementary resistance monitoring tool. The data on general surveillance do not indicate any unanticipated adverse effects on human and animal health or the environment arising from the cultivation of maize MON 810. EFSA reiterates its recommendations on the methodology and analysis of farmer questionnaires, and considers that future literature searches on maize MON 810 performed in the context of annual PMEM reports should follow the guidelines given in the 2017 EFSA explanatory note on literature searching. Moreover, EFSA encourages relevant stakeholders to implement a methodological framework that enables the use of existing networks in the broader context of environmental monitoring. EFSA concludes that no new evidence has been reported in the 2016 PMEM report that would invalidate previous EFSA evaluations on the safety of maize MON 810.

Relevance of new scientific evidence on the occurrence of teosinte in maize fields in Spain and France for previous environmental risk assessment conclusions and risk management recommendations on the cultivation of maize events MON810, Bt11, 1507 and GA21

Relevance of new scientific evidence on the occurrence of teosinte in maize fields in Spain and France for previous environmental risk assessment conclusions and risk management recommendations on the cultivation of maize events MON810, Bt11, 1507 and GA21

Farm‐level GM Coexistence Policies in the EU: Context, Concepts and Developments

SummaryMany EU MS have implemented coexistence policies to govern the cultivation of GM crops on their territory but only one GM crop, the Bt maize event MON810, is currently cultivated in the EU. From a practical point of view, a combination of paper traceability and implementation of isolation distances between GM and non‐GM maize are considered as being the most effective way of segregating both types of materials. In general, infringements will however only become apparent after harvesting the crops. Liability issues will then be invoked late in the process restricting or at least limiting flexibility in the marketing of the materials in an appropriate way. Nevertheless, following the general guidelines for coexistence developed by the European Commission, EU Member States are progressively regulating coexistence at the national level. The policies in the EU governing coexistence can be differentiated into ex‐ante regulations and ex‐post liability rules. This differentiation is useful as the economic implications between the two differ. With regard to maize, studies show that the costs of complying with the given threshold values for GM content at farm level range from zero to 2 per cent of the total growing costs for both conventional and organic production.

Cry1Ab protein from Bacillus thuringiensis and MON810 cry1Ab-transgenic maize exerts no adjuvant effect after airway exposure.

The genetically modified (GM) maize event MON810 has been inserted with a processed version of the transgene, cry1Ab, derived from the soil bacterium Bacillus thuringiensis (Bt) to express proteins with insecticidal properties. Such proteins may introduce new allergens and also act as adjuvants that promote allergic responses. While focus has been on safe consumption and hence the oral exposure to GM food and feed, little is known regarding inhalation of pollen and desiccated airborne plant material from GM crops. The aim of this study was to investigate whether plant material from the Cry1Ab-expressing maize variety MON810, or trypsin-activated Cry1Ab (trypCry1Ab) protein produced in recombinant bacteria, may act as adjuvants against the allergen ovalbumin (OVA) in a mouse model of airway allergy. A clear proallergic adjuvant effect of the mucosal adjuvant cholera toxin (CT) was demonstrated, determined as increased specific IgE, eosinophils and Th2 cytokines in MLN cell supernates, while no elevation in OVA-specific antibodies or cytokine release from MLN cells after stimulation with OVA were observed in mice receiving Cry1Ab-containing plant materials or the trypCry1Ab protein. Our data suggest that Cry1Ab proteins had no detectable systemic adjuvant effect in mice after airway exposure. Further experiments with purified plant proteins, as well as long-term exposures needs be conducted to further evaluate exposures experienced in real-life situations.

Monitoring of genetically modified food and feed in the Tunisian market using qualitative and quantitative real-time PCR

Genetically modified organisms (GMO) invade more and more the agricultural production in the world. Although there are no legislations on GM labeling and cultivation of GM crops in Tunisia, the present study aims to check the status of GMO in Tunisian market using qualitative and quantitative real time-PCR (QRT-PCR). Three-hundred-sixty five samples were collected and different DNA extraction methods were adapted and optimized. Specific primers targeting 35S promoter from Cauliflower mosaic virus (CaMV) and nopaline synthase terminator from Agrobacterium tumefaciens (At) were used for the detection of the GMO insert and Taxon specific primers for the detection of plant species. Validated Taqman® probes (EU-RL) targeting event specific regions of the maize events MON810, Bt11, and the soybean event RRS were used for the quantification studies. Seven food and feed products showed different amounts of RRS (1.9%), MON810 (2.1%), and Bt11 (1.6%). The results demonstrate for the first time the presence of GMO in Tunisian markets reinforcing the need for the development of accurate quantitative methods in routine analyses.

Interlaboratory Study of Qualitative PCR Methods for Genetically Modified Maize Events MON810, Bt11, GA21, and CaMV P35S

Qualitative PCR methods for the genetically modified (GM) maize events MON810, Bt11, and GA21, and the 35S promoter (P35S) region of the cauliflower mosaic virus (CaMV) were evaluated in an interlaboratory study. Real-time PCR-based quantitative methods for these GM events using the same primer pairs had already been validated in previous studies. Fifteen laboratories in Japan participated in this interlaboratory study. Each participant extracted DNA from blind samples, performed qualitative PCR assays, and then detected the PCR products with agarose gel electrophoresis. The specificity, sensitivity, and false-negative and false-positive rates of these methods were determined with different concentrations of GM mixing samples. LODs of these methods for MON810, Bt11, GA21, and the P35S segment calculated as the amount of MON810 were 0.2, 0.2, 0.1, and 0.2% or less, respectively, indicating that the LODs of MON810, Bt11, and P35S were lower than 10 copies, and the LOD of GA21 was lower than 25 copies of maize haploid genome. The current study demonstrated that the qualitative methods would be fit for the detection and identification of these GM maize events and the P35S segment.

LT-RADE: An Efficient User-Friendly Genome Walking Method Applied to the Molecular Characterization of the Insertion Site of Genetically Modified Maize MON810 and Rice LLRICE62

Information on the insertion site and characterization of the transgene(s) in genetically modified organisms (GMO) is very important for safety assessment and identification of a GMO. The generation of such information in general and in particular in emergencies or rapid alert situations involving GMO greatly benefit from the availability of simple, efficient, and rapid approaches. Here, we report on the improvement of a restriction independent method named “Rapid Amplification of genomic DNA Ends” (RADE). The method was developed using maize event MON810 genomic DNA as a model system, testing a standard Taq polymerase or a blend of polymerases (standard Taq and proofreading Tgo polymerases (LT-RADE)). Both methods produce an initial single strand DNA, followed by nested PCR steps and yield easy-to-isolate DNA fragments for further manipulation. We showed that the application of the Taq/Tgo polymerase blend significantly increased the size of the obtained PCR products. Using LT-RADE, we could successfully isolate the flanking regions of the transgenic insert of the GM maize event MON810 and confirmed the existing data on the adjacent regions of the insert. In addition, application of our approach allowed to efficiently isolate and identify, for the first time, the DNA sequences surrounding the insert of GM rice event LLRICE62.

Commentary to Publications in Food Analytics Methods Journal as Related to Genetic Stability of Maize Event MON810

Wewould like to expresssome commentsontwo publicationsrelated to genetic stability of MON810 published in thisJournal (Aguilera et al. 2008, 2009). In the first publication(Aguilera et al. 2008), it is reported that “Twenty-four out ofthe 26 analyzed varieties met the expected stability features.One variety gave negative results in all assays, and onevariety contained the necessary genetic elements for express-ing CryIA(b) protein although giving negative results for thelong PCR product. To our knowledge, this study is the firstpost-marketing stability analysis performed on GM commer-cial seed varieties”. In the second publication (Aguilera et al.2009), it is also reported that “Global results assessed andguaranteed the genetic intactness of the transgenic integrationper haploid genome for 24 out of the 26 commercial varietiesstudied, which showed no significant differences between2(-Delta Delta CT) values respect to the calibrator value.Conversely,twovarietiesshowednointacttransgenicinsertintheir genomes. This validated analytical method was suitablefor MON 810 detection and quantification purposes.”Upon our request, the authors informed us that theSpanish Instituto Nacional de Investigacion y TecnologiaAgraria y Alimentaria (www.inia.es) provided the JRC with26 MON810 maize varieties, without however providingdetails of the respective batch numbers. We can confirmthat the two deviating results are not related to intacttransgenic insertion as reported by the authors. Afterinvestigation, the conclusions were that the two varieties(entry 2 and entry 5) were in fact not MON810 maize.Variety CGS4540 (entry 5) was a Bt176 maize hybrid, andwe do not understand why the seed were provided asMON810. With regard to entry 2 (designated as Aristis Bt),we requested the Spanish Ministry to send a sample ofAristis Bt to its official Spanish laboratory CSIC for testing.The results were positive for MON810, as expected.However, the material that was provided to the JRC wasmostlikelyAristis,theconventionalcounterpartofAristisBt(MON810). The authors were not able to provide a correctchain of custody for the samples used in their analysesallowing to resolve the origin of these deviating results.The industry has invested significantly to provide qualityproducts to the marketplace, which includes selling com-pliant and stable products. Traits are tested for presenceand stability for many generations prior to release to themarket place. We are of the opinion that there is noscientific evidence for MON810 instability.