GM Crop Database

Database Product Description

MON89788 (MON-89788-1)
Host Organism
Glycine max (Soybean)
Trade Name
Roundup RReady2Yield™
Trait
Glyphosate herbicide tolerance.
Trait Introduction
Agrobacterium tumefaciens-mediated plant transformation.
Proposed Use

Production for human consumption and livestock feed.

Product Developer
Monsanto Company

Summary of Regulatory Approvals

Country Food Feed Environment Notes
Argentina 2016 2016 2016
Australia 2008 2008
Canada 2007 2007 2007
China 2008 2008
Colombia 2010 2010
European Union 2008 2008
Indonesia 2011
Japan 2008 2008 2008
Korea 2009 2009
Malaysia 2012 2012
Mexico 2008 2008
New Zealand 2008
Philippines 2007 2007
Russia 2010 2010
Singapore 2014
South Africa 2013 2013
Taiwan 2007
Turkey 2011
United States 2007 2007 2007
Uruguay 2009
Vietnam 2014 2014

Introduction Expand

The soybean line MON98788 was developed to allow for the use of glyphosate, the active ingredient in the herbicide Roundup®, as a weed control option for soybean. This genetically engineered soybean variety contains a glyphosate tolerant form of the plant enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) isolated from the common soil bacterium, Agrobacterium tumefaciens strain CP4 (CP4 EPSPS).

The EPSPS enzyme is part of the shikimate pathway that is involved in the production of aromatic amino acids and other aromatic compounds in plants. When conventional plants are treated with glyphosate, the plants cannot produce the aromatic amino acids needed to survive. This enzyme is present in all plants, bacteria, fungi, but not in animals, which do not synthesize their own aromatic amino acids. Because the aromatic amino acid biosynthetic pathway is not present in mammalian, avian or aquatic life forms, glyphosate has little if any toxicity for these organisms. The EPSPS enzyme is normally present in food derived from plant and microbial sources.

MON89788 was developed by introducing the CP4 EPSPS gene into a commercial soybean variety using Agrobacterium tumefaciens-mediated transformation of meristem-derived material from soybean variety A3244. A3244 is an elite maturity group III soybean variety which was developed and selected for transformation based on its superior agronomic performance over other soybean lines.

Summary of Introduced Genetic Elements Expand

Code Name Type Promoter, other Terminator Copies Form
CP4 epsps 5-enolpyruvyl shikimate-3-phosphate synthase HT

P-FMV/TSF1: chimeric promoter containing Arabidopsis thaliana tsf1 promoter

elongation factor EF-1 alpha; Figwort Mosaic Virus 35S promoter enhancer; A. thaliana tsf1 leader and intron; chloroplast transit peptide from A. thaliana

Pisum sativum T-E9 DNA containing 3’ UTR of Rubisco small subunit E9 gene

1

Characteristics of Glycine max (Soybean) Expand

Center of Origin Reproduction Toxins Allergenicity

Southeast Asia; wild soybean species endemic in China, Korea, Japan, Taiwan.

Self-polinated; rarely displays any dormancy characteristics; does not compete well with other cultivated plants.

Raw soybeans contain trypsin inhibitors, which are toxin when eaten.

Soy allergies are common, and eating soy products can cause rashes and swelling of the skin in sensitive individuals.

Donor Organism Characteristics Expand

Latin Name Gene Pathogenicity
Agrobacterium tumefaciens strain CP4 CP4 epsps

Agrobacterium tumefaciens is a common soil bacterium that is responsible for causing crown gall disease in susceptible plants. There have been no reports of adverse effects on humans or animals.

Modification Method Expand

Soybean line MON89788 was produced by Agrobacterium tumefaciens-mediated transformation of meristematic tissue from soybean cultivar A3244. The plasmid PV-GMGOX20 used for transformation contained the aroA (epsps) gene from A tumefaciens strain CP4 encoding the CP4 EPSPS protein for glyphosate tolerance. Expression of the CP4 EPSPS gene was regulated by a chimeric promoter combining the enhancer sequences from the 35S promoter of the Figwort Mosaic Virus and the promoter from the Tsf1 gene from Arabidopsis thaliana, which codes for the elongation factor, EF-1 alpha. A chloroplast transit peptide (CTP2) coding sequence from the ShkG gene of A. thaliana facilitated the translocation of newly translated EPSP synthase into chloroplasts, the site of aromatic amino acid biosynthesis and glyphosate's site of action. The 3’ nontranslated sequence from the ribulose-1, 5-bisphosphate carboxylase small subunit (RbcS2) E9 gene of pea (Pisum sativum) provided the transcriptional termination sequences. This cassette, coding for the expression of the CP4 EPSPS enzyme, was contained between the Right and Left Border sequences of the T-DNA region in PV-GMGOX20.

Characteristics of the Modification Expand

The Introduced DNA

Southern blot analysis of genomic DNA from MON89788 demonstrated that there is a single copy of the T-DNA from PV-GMGOX20 integrated at a single locus in the genome. Hybridisation with different probes confirmed that the integrated T-DNA contains all of the components from the EPSPS expression cassette between the Left Right and Left Borders. Lack of hybridisation with the probes made from the plasmid backbone confirmed the absence of any of these sequences in MON89788. The organization of the genetic elements within the insert of MON89788 was confirmed by DNA sequence analysis, using PCR primers to amplify three overlapping DNA fragments spanning the entire length of the insert. Sequencing of the amplified fragments confirmed that the arrangement of the genetic elements is identical to that in PV-GMGOX20.

Genetic Stability of the Introduced Trait

DNA analyses over four generations demonstrated that the cp4 epsps gene was stably inserted. Hybridisation probes spanning the entire T-DNA region were used to ensure that the cassette was stably inherited and the absence of any backbone sequences was confirmed by hybridisation using probes from this region of the plasmid. The glyphosate tolerance trait was also evaluated during the development of MON89788. The R0 transgenic plant was self-pollinated and the R1 population was evaluated for glyphosate tolerance, showing the expected ratio of 3:1 resistant to susceptible plants. Selected R1 plants that survived glyphosate treatment were analysed using quantitative PCR to identify a single plant homozygous for the cp4 epsps gene, which was self pollinated to provide the R2 generation. Testing of this population, and the R3 generation, confirmed that 100% of the plants were tolerant to glyphosate.

Expressed Material

Expression of the cp4 epsps gene results is a single 455 amino acid polypeptide of 47.6 kDA, which was characterized using (1) SDS-PAGE, (2) western immunoblot, (3) N-terminal sequence analysis, (4) MALDI-TOF mass spectrometry, (5) enzymatic activity analysis, and (6) glycosylation analysis. The plant expressed protein was compared with the same protein produced in E. coli in order to establish equivalence to existing standards used for safety evaluation of CP4 EPSPS. All of the tests used produced comparable results between the plant expressed and the E. coli expressed proteins, thus establishing the equivalence of the proteins from the two sources.

CP4 EPSPS protein levels in tissues derived from MON89788 were determined by a validated ELISA assay. MON89788 tissues were collected from replicated field trials across five US field locations in 2005 and CP4 EPSPS protein levels from a range of tissues was determined. CP4 EPSPS protein levels in grain averaged 140 µg/g fresh weight and 62 µg/g fresh weight in leaves.

Environmental Safety Considerations Expand

Field Testing

Field trials were conducted at 17 locations during 2005 to thoroughly evaluate phenotypic, agronomic and ecological interactions of MON89788 and compare these to A3244, the conventional parental line, and other commercially available soybeans. These 17 locations provided a diverse range of environmental and agronomic conditions representative of the majority of commercial soybean production regions in the US. Plant growth stage was assessed several times during the growing season and observational data on the presence of various biotic and abiotic stresses, together with the response of the lines to these stresses was recorded.

A total of 11 different phenotypic characters was evaluated and the only significant difference detected in across-site analyses was a reduced height for MON89788 compared to A3244. The difference falls within the range of values observed for commercial soybean varieties. No differences were observed in susceptibility to pests and diseases, neither were there any differences observed in numbers of beneficial insects and spiders collected from the sites. Seed dormancy and germination characteristics were determined across a range of conditions with seed produced during the 2005 trials at three different locations.

Outcrossing

Gene introgression from transformed soybean line MON89788 is considered as extremely unlikely as there are no relatives of cultivated soybean in the continental United States and soybean plants are almost completely self-pollinated. Furthermore, the reproductive characteristics such as pollen production and viability were unchanged by the genetic modification resulting in MON89788.

Cultivated soybean, Glycine max, naturally hybridizes with the wild annual species G. soja. However, G. soja is only found naturally occurring in China, Korea, Japan, Taiwan and the former USSR, and is not naturalized in North America, although it may possibly be grown in research plots. It was concluded that the potential for transfer of the glyphosate tolerance trait from the transgenic line to soybean relatives through gene flow was negligible in managed ecosystems, and that there was no potential for transfer to wild species in continental United States.

Weediness Potential

No competitive advantage was conferred to MON89788, other than that conferred by resistance to glyphosate herbicide. The only phenotypic difference between MON89788 and the parental line was a slightly decreased plant height, which was within the range of commercial soybean was not expected to result in an increase in weediness potential. Resistance to glyphosate-containing herbicides will not, in itself, render soybean weedy or invasive of natural habitats since none of the reproductive or growth characteristics were modified. In the unlikely event of the formation of a herbicide tolerant hybrid, there would be no competitive advantage conferred on any hybrid progeny in the absence of sustained glyphosate use. The glyphosate-tolerant plant could easily be controlled by mechanical means or by using herbicides that are not based on glyphosate. Cultivated soybean does not exhibit any weedy characteristics in the United States, although related species are reported as weeds in Japan and China. It was concluded that soybean line MON89788 had no altered weed of invasiveness potential compared to commercial soybean varieties.

Secondary and Non-Target Adverse Effects

Field observations of line MON89788 revealed no effects on pest or beneficial insects and spiders, suggesting that the levels of CP4 EPSPS in the transgenic plant tissues were not toxic to arthropods. The novel protein CP4 EPSPS did not result in altered toxicity or allergenicity properties as demonstrated from studies including the acute oral mouse gavage study, the digestive fate study, and the fact that homologous EPSPS proteins are ubiquitous in nature and common in plants, fungi and microbes. Furthermore, the high specificity of the enzyme for its substrates makes it unlikely that the introduced enzyme would metabolize endogenous substrates to produce compounds toxic to beneficial organisms. It was determined that the genetically modified soybean line MON89788 did not have a significant adverse impact on organisms beneficial to plants or agriculture, or on nontarget organisms, and was not expected to impact on threatened or endangered species.

Impact on Biodiversity

Analysis of available information indicates that MON 89788 exhibits no traits that would cause increased weediness, that its unconfined cultivation should not lead to increased weediness of other sexually compatible relatives (of which there are none in the United States), and it is likely to have no effect on non-target organisms common to the agricultural ecosystem or threatened or endangered species recognized by the U.S. Fish and Wildlife Service. Based on this analysis, there is no apparent potential for significant impact to biodiversity.

Food and/or Feed Safety Considerations Expand

Dietary Exposure

Estimated levels of potential exposure to the CP4 EPSPS enzyme from MON89788 were calculated using a Dietary Exposure Evaluation Model and food consumption data from the USDA survey of individual food intake. Assuming that all soybean food items consumed were derived from MON89788 soybeans, the 95th percentile for acute dietary intake would be 9.9 µg/kg body weight for adults and 391 µg/kg bodyweight for non-nursing infants. It is considered that the genetic modification of MON89788 soybean will not result in any change in the consumption pattern of soybean products. In particular, over 90% of soybean grown in the United States already contains the same CP4 EPSPS protein present in MON89788, which has been extensively evaluated prior to approval in 1996. Furthermore, experience of safe use has been shown with this protein, which is present in Roundup Ready soybean and corn that has been widely grown around the world for more than ten years. Dietary exposure to EPSPS is not novel in that all plants, bacteria and fungi produce this enzyme and the CP4 EPSPS will be ingested as inactive denatured protein since all soybean-derived human food products are heated prior to consumption.

Toxicity and Allergenicity

The potential for toxicity of the CP4 EPSPS protein from MON89788 was evaluated by examining the amino acid sequence homology to known toxins, acute oral toxicity studies on mice, and the characteristics and source of the protein. The amino acid sequence of CP4 EPSPS was determined to be closely related to the sequence of the endogenous soybean EPSPS enzyme. An analysis of the amino acid sequence of the inserted CP4 EPSPS enzyme did not show homologies with known mammalian protein toxins, contained in a sequence databases TOXIN5, and was not judged to have any potential for human toxicity. Acute oral toxicity studies with purified CP4 EPSPS did not reveal any deleterious effects when mice were administered a dose of 572 mg/kg body weight, which was approximately 1500-fold greater than the 95th percentile for acute dietary intake calculated for non-nursing infants. Furthermore, EPSPS is an enzyme that is ubiquitous in nature, present in plants, fungi and micro-organisms and therefore would not be expected to be toxic or allergenic and the donor organism, Agrobacterium tumefaciens strain CP4 is not a known human or animal pathogen.

A search for amino acid sequence similarity between the CP4 EPSPS protein and known allergens revealed no significant amino acid sequence homologies. In addition, the potential for allergenicity was assessed based upon the characteristics of known food allergens (stability to digestion, stability to processing). Unlike known protein allergens, CP4 EPSPS was rapidly degraded by acid and/or enzymatic hydrolysis when exposed to simulated gastric or intestinal fluids with more than 95% of the protein digestions within 15 seconds in simulated gastric fluids. Overall, the CP4 EPSPS does not possess characteristics typical of known protein allergens and there are no reports of allergy to A. tumefaciens strain CP4, the source of the protein

Soybean is known to contain endogenous allergens which elicit an allergic response in a small number of individuals. To assess whether the transformation process may have increased the overall allergenicity of MON89788 compared to conventional soybean, an IgE-binding ELISA study was conducted. Sera used for the assays was obtained from 16 individuals with IgE-mediated allergy to soy and six non-allergic individuals and the assays were performed with extracts from MON89788, A3244 (the parental non-transgenic line) and 24 commercial soybean varieties. The study showed no greater allergic potential from MON89788 than from the other non-transgenic soybean varieties which are currently all present on the market.

Nutritional Data

Compositional analyses were conducted to assess whether the nutrient and anti-nutrient levels in grain and forage tissues derived from MON89788 were comparable to those from A3244, the conventional parental line. An additional 12 conventional soybean varieties were included in the comparison to establish a range of natural variability and define a tolerance interval for each particular analyte. Grain and forage tissues were collected from MON89788 and A3244 grown in three replicated plots at each of five trial sites across the US during 2005.

A total of 42 components were analysed in grain samples, including proximates (protein, fat, ash, fibre and moisture), amino acids, fatty acids, anti-nutrients, isoflavones and vitamins. Statistical significance was declared at the 5% level and the only differences between MON89788 and A3244 grain were in the levels for Vitamin E and the isoflavoes daidzein and glycitein. These differences were small (1.6-11%) and all fell within the 99% tolerance levels established for these parameters calculated from the analysis of the conventional varieties. Forage samples were analysed for proximates and the only significant difference was in moisture level, which once again was within the 99% tolerance interval calculated from the analysis of conventional varieties. From these results it was concluded that MON89788 is compositionally equivalent to conventional soybeans.

Abstract Collapse

Soybean (Glycine max) was grown as a commercial crop in 84 countries in 2006 with a combined harvest of 220 million metric tonnes. The major producers of soybeans were the United States, Brazil, Argentina, China, India, Paraguay and Canada. Soybean is grown primarily for its seed which has many uses in the food and industrial sectors, and represents one of the major sources of edible vegetable oil and of proteins for livestock feed use.

A major food use of soybean in North America and Europe is as purified oil, used in margarines, shortenings, and cooking and salad oils. It is also a major ingredient in food products such as tofu, tempeh, soya sauce, simulated milk and meat products, and is a minor ingredient in many processed foods. Soybean meal is used as a supplement in feed rations for livestock.

Weeds are a major production problem in soybean cultivation. Typically, weeds are managed using a combination of cultural (e.g. seed bed preparation, using clean seed, variety selection, and planting date) and chemical controls. Depending on the production area and the prevalent weed species, herbicides may be applied before planting (e.g. pendimethalin, trifluralin, metribuzin), after planting but before emergence (e.g. pendimethalin, linuron, imazethapyr), and/or after emergence (e.g. bentazon, acifluorfen, fomesafen). Commonly, several different herbicides are required to adequately control weeds in soybean fields.

The soybean line MON89788 was developed to allow for the use of glyphosate, the active ingredient in the herbicide Roundup®, as a weed control option. This genetically engineered soybean line contains a form of the plant enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) that allows MON89788 to survive the otherwise lethal application of glyphosate. The EPSPS gene put into MON89788 was isolated from a strain of the common soil bacterium Agrobacterium tumefaciens called CP4 and the form of EPSPS enzyme produced by this gene is tolerant to glyphosate. This gene is the same as that used in the first glyphosate-tolerant soybean line GTS-40-3-2, however a different promoter has been used in MON88788 – a chimeric promoter containing the Figwort Mosaic Virus 35S enhancer and the promoter from the Arabidopsis thaliana tsf1 elongation factor EF-1 alpha.

The EPSPS enzyme is part of an important biochemical pathway in plants called the shikimate pathway, that is involved in the production of aromatic amino acids and other aromatic compounds. When conventional plants are treated with glyphosate, the plants cannot produce the aromatic amino acids needed to grow and survive. EPSPS is present in all plants, bacteria, and fungi. It is not present in animals, which do not synthesize their own aromatic amino acids. Because the aromatic amino acid biosynthetic pathway is not present in mammals, birds or aquatic life forms, glyphosate has little if any toxicity for these organisms. The EPSPS enzyme is naturally present in foods derived from plant and microbial sources.

MON89788 was developed by introducing the CP4 EPSPS gene into a commercial soybean variety using Agrobacterium tumefaciens-mediated transformation of meristem-derived material from soybean variety A3244. A3244 is an elite maturity group III soybean variety which was developed and selected for transformation based on its superior agronomic performance over other soybean lines.

MON89788 has been tested in field trials in the United States, starting in 2001. MON89788 soybean plants have been evaluated extensively to confirm that they exhibit the desired agronomic characteristics, that tolerance to glyphosate is stable under field conditions, and that they do not present a plant pest risk. The field tests were conducted in agricultural settings under physical and reproductive confinement conditions.

Soybean does not have any weedy relatives with which it can crossbreed in the continental United States and Canada. Cultivated soybean can naturally cross with the wild annual species G. soja, however G. soja, which occurs naturally in China, Korea, Japan, Taiwan and the former USSR, is not naturalized in North America. Additionally, soybean plants are almost completely self-pollinated and reproductive characteristics such as pollen production and viability were unchanged by the genetic modification resulting in MON89788. It was therefore concluded that the potential for transfer of the glyphosate tolerance trait from the transgenic line to soybean relatives through gene flow (outcrossing) was negligible in managed ecosystems, and that there was no potential for transfer to wild species in Canada and the continental United States.

The food and livestock feed safety of MON89788 soybean was established based on the lack of any sequence homology between the CP4 EPSPS protein and known toxin sequences; the fact that CP4 EPSPS protein constitutes a small amount of the protein in MON89788 soybeans so there is little dietary exposure; the lack of toxicity or allergenicity of EPSPS proteins from plants, bacteria and fungi; and by direct laboratory studies of the CP4 EPSPS protein. The nutritional equivalence and wholesomeness of MON89788 soybeans compared to conventional (non-GM) soybeans was demonstrated by the analysis of key nutrients, including proximates (e.g. protein, fat, fibre, ash, and carbohydrates), amino acid and fatty acid composition, as well as anti-nutrients.

Links to Further Information Expand

Canadian Food Inspection Agency European Food Safety Authority Food Standards Australia New Zealand Health Canada Novel Foods Japanese Biosafety Clearing House, Ministry of Environment Philippines Department of Agriculture, Bureau of Plant Industry U.S. Department of Agriculture, Animal and Plant Health Inspection Service United States Food and Drug Administration

This record was last modified on Monday, July 31, 2017