Novel food information: Glyphosate tolerant soybean MON 89788

On this page

• Background
• Introduction
• Development of the modified plant
• Characterization of the modified plant
• Product information
• Dietary exposure
• Nutrition
• Chemistry/toxicology
• Conclusion

Background

Health Canada has notified Monsanto Canada Inc. that it has no objection to the food use of Glyphosate Tolerant soybean (MON 89788). The Department conducted a comprehensive assessment of these varieties according to its Guidelines for the Safety Assessment of Novel Foods (September 1994). These Guidelines are based upon internationally accepted principles for establishing the safety of foods with novel traits.

The following provides a summary of the notification from Monsanto Canada Inc. and the evaluation by Heath Canada and contains no confidential business information.

Introduction

Soybean line MON 89788 was genetically modified using recombinant DNA techniques to introduce the CP4 5-enolpyruvylshikimate-3-phosphate synthase (cp4 epsps) coding sequence derived from the common soil bacterium Agrobacterium sp. strain CP4. The sequence codes for the CP4 EPSPS enzyme which is functionally equivalent to the native soybean EPSPS, except that is naturally tolerant to inhibition by glyphosate herbicide. Health Canada has previously indicated no objection to the sale of glyphosate tolerant corn (603, MON 802, MON 832, 88017), cotton (1445, 88913), canola (GT 200, GT 73), Sugarbeet (H7-1) and soybean (40-3-2) lines for human food applications in Canada.

The assessment conducted by Food Directorate evaluators determined how MON 89788 soybean was developed; how the composition and nutritional quality of MON 89788 soybeans compared to non-modified varieties; and what the potential is for MON 89788 soybeans to be toxic or cause allergic reactions. Monsanto has provided data which demonstrates that MON 89788 soybeans are as safe and of the same nutritional quality as traditional soybean varieties used as food in Canada.

The Food Directorate has a legislated responsibility for pre-market assessment of novel foods and novel food ingredients as detailed in the Food and Drug Regulations (Division 28). Food use of MON 89788 soybean is considered a novel food under the following part of the definition of novel foods:

" c) a food that is derived from a plant, animal or microorganism that has been genetically modified such that

1. the plant, animal or microorganism exhibits characteristics that were not previously observed in that plant, animal or microorganism."

Development of the modified plant

The petitioner has provided information describing the methods used to develop MON 89788 soybean and molecular biology data that characterize the genetic change which confers tolerance to glyphosate herbicides. Commercial soybean variety A3244 was genetically modified using Agrobacterium tumefaciens transformation. The transforming plasmid PV-GMGOX20 carried a transfer DNA (T-DNA) sequence comprised of a cp4-epsps gene cassette. The cp4-epsps gene cassette contained a chimeric promoter containing the promoter of the tsf1 gene from Arabidopsis thaliana combined with the enhancer sequences from the Figwort Mosaic virus 35S promoter (P-FMV/TSF1), the untranslated leader (exon1) sequence from the A. thaliana tsf1 (L-TSF1), the intron from tsf1 gene (I-TSF1), the chloroplast transit peptide sequence from A. thaliana (TS-ctp2), the coding region of cp4 epsps from Agrobacterium sp. strain (CR-cp4 epsps) and the nontranslated region of the Pisum sativum rbcE9 gene (T-E9).

Characterization of the modified plant

Southern blot analysis of MON 89788 demonstrated the insertion of a single copy of the cp4 epsps cassette in the soybean genome at a single locus. Southern blot analysis also demonstrated the integrity of the cp4 epsps gene and its regulatory elements. Southern blot analysis also demonstrated, as expected, the absence of any plasmid derived sequences outside the T-DNA region, such as the spectinomycin resistance gene found in the plasmid backbone. The elements contained in the cp4epsps cassette have been shown to be stable with no rearrangements through Southern, PCR and sequence analysis. These analyses of the insert show that the cassette is entirely integrated into the genome and that all the elements are intact.

The stability of the inserted cp4-epsps cassettes was evaluated in several generations of soybean grown at separate locations. The results of Southern blot analysis and segregation data demonstrated the stability of the MON 89788 at the genomic level in different environments.

Confirmation of the CP4 EPSPS protein identity was generated using MALDI-ToF and supported by N-terminal sequence analysis. Protein expression levels determined through ELISA showed that CP4 EPSPS represented 0.037% of the total dry weight of MON 89788 grain.

Product information

MON 89788 differs from its traditional counterpart by the addition of a cp4-epsps gene sequence and its associated regulatory elements into the genome, and the expression of the CP4 EPSPS protein. The protein encoded by this gene is expressed at different levels in the plant tissue.

Dietary exposure

MON 89788 is expected to be used in similar applications as traditional soybean varieties by the food industry. Refined, bleached, and deodorized soybean can be further processed to produce cooking oils, shortening, margarine, mayonnaise, salad dressings, and a wide variety of products that are either based entirely on fats and oils or contain fat or oil as a principal ingredient. Soy protein isolate is also used in such foods as soups, sauce bases, energy bars, nutritional beverages, infant formula, and dairy replacements.

Nutrition

The nutrient data pertaining to glyphosate herbicide tolerant soybean MON 89788 were obtained from a study conducted in 2005. The treatment included seed from transgenic event MON 89788 and its control A3244. The control A3244 soybean was genetically identical to MON 89788 except that it did not express the CP4 EPSPS protein.

The soybean samples were analyzed for proximates, amino acids, fatty acids, vitamin E, and secondary metabolities and antinutrients (isoflavones, lectins, stachyose, raffinose, phytic acid and trypsin inhibitor). Samples of soybean meal were analysed for calcium, copper, iron, magnesium, manganese, molybdenum, phosphorus, potassium and zinc.

The chemical and nutritional composition of the soybean from transgenic and non-transgenic samples were comparable. For the few comparisons where the differences were statistically significant, nutritionally they were considered not important and the values fall within the ranges established in the literature.

Chemistry/toxicology

The novel gene present in MON 89788 soybean was not isolated from a known pathogen. The novel gene generates a protein that is not considered likely to be a toxin, based on the absence of acute oral toxicity in mice, at a dose that was 3 to 4 orders of magnitude greater than the hypothetical level of intake of the protein from this crop in the human diet. In addition, the novel protein bears no biologically significant homology to any known toxin or pharmacological agent. Lastly, very similar proteins have been incorporated in other transgenic plants for a number of years with no reported cases of toxicity associated with the consumption of food products derived from these transgenic plants.

The novel protein is not considered likely to be an allergen since it does not share the characteristics of protein that are food allergens. Unlike many food allergens, the novel protein constitutes a negligible amount of the total protein in foods that contain it. The amino acid sequence of the novel protein has no significant homology to any known allergen. The novel protein is rapidly degraded in a simulated gastric fluid and in simulated intestinal fluid systems, as detected by western blot analysis. These results suggest that the novel protein would be digested in the mammalian digestive tract.

The novel plant and the non-transgenic plant strain from which it is derived do not contain significantly different amounts of biologically active endogenous substances, including phytoestrogens. The novel plant does not contain endogenous allergens that are altered in terms of IgE binding ability, when compared to 24 commercial soybean varieties. Therefore, in this regard the novel plant does not possess any apparent additional health concern when compared to the non-transgenic plant variety from which it was derived.

Conclusion

Health Canada's review of the information presented in support of the food use of MON 89788 soybean does not raise concerns related to food safety. Health Canada is of the opinion that food derived from MON 89788 soybean is as safe and nutritious as food from current commercial soybean varieties.

Health Canada's opinion deals only with the food use of MON 89788 soybean. Issues related to its use as animal feed have been addressed separately through existing regulatory processes in the Canadian Food Inspection Agency.

This Novel Food Information document has been prepared to summarize the opinion regarding the subject product provided by the Food Directorate, Health Products and Food Branch, Health Canada. This opinion is based upon the comprehensive review of information submitted by the petitioner according to the Guidelines for the Safety Assessment of Novel Foods (September 1994).

For further information, please contact:

Novel Foods Section
Food Directorate
Health Products and Food Branch
Health Canada, PL2204A1
251 Frederick Banting Driveway
Ottawa, Ontario K1A 0K9
bmh-bdm@hc-sc.gc.ca