GM Crop Database

Database Product Description

GA21 x MON810 (MON-ØØØ21-9 x MON-ØØ81Ø-6)

Host Organism: Zea mays (Maize)

Trait: Resistance to lepidopteran pests and glyphosate herbicide tolerance

Trait Introduction: Traditional plant breeding and selection

Proposed Use: Production for human consumption and livestock feed.

Product Developer: Monsanto Company

Summary of Regulatory Approvals

Country	Food	Feed	Notes
European Union	2005	2005	View Notified as an existing product on 6 October 2004. Notification expired on 18 April 2007, no application for renewal thus authorisation no longer valid.
Japan	2003	2003
Korea	2004
Philippines	2004	2004
South Africa	2003	2003

Summary of Introduced Genetic Elements Expand

Code	Name	Type	Promoter, other	Terminator	Copies	Form
epsps	5-enolpyruvyl shikimate-3-phosphate synthase	HT	rice actin I promoter and intron sequences ; ribulose-1,5-bisphosphate carboxylase oxygenase (RuBisCo) derived chloroplast transit peptide squences (from corn & sunflower)	A. tumefaciens nopaline synthase (nos) 3'-untranslated region	3*	Modified by in vitro mutagenesis; single insertion site with 3 complete copies of EPSPS cassette plus 3 incomplete copies
cry1Ab	Cry1Ab delta-endotoxin (Btk HD-1)	IR	enhanced CaMV 35S, maize HSP70 intron	None. Lost through 3' truncation during integration	1	Truncated

Characteristics of Zea mays (Maize) Expand

Center of Origin	Reproduction	Toxins	Allergenicity
Mesoamerican region, now Mexico and Central America	Cross-pollination via wind-borne pollen is limited, pollen viability is about 30 minutes. Hybridization reported with teosinte species and rarely with members of the genus Tripsacum.	No endogenous toxins or significant levels of antinutritional factors.	Although some reported cases of maize allergy, protein(s) responsible have not been identified.

Donor Organism Characteristics Expand

Latin Name	Gene	Pathogenicity
Bacillus thuringiensis subsp. kurstaki	EC2.4.2.19	While target insects are susceptible to oral doses of Bt proteins, no evidence of toxic effects in laboratory mammals or birds given up to 10 µg protein/g body weight.

Abstract Collapse: GA21 X MON810 (OECD identifier: MON-ØØØ21-9 x MON-ØØ81Ø-6) maize is an F1 hybrid resulting from the hybridization of the herbicide-tolerant maize inbred GA21 (MON-ØØØ21-9) with the insect-resistant maize inbred MON810 (MON-ØØ81Ø-6). This stacked maize hybrid is a product of traditional plant breeding, and therefore is not automatically subject to regulation in all jurisdictions as are transgenic plants resulting from recombinant DNA technologies. Certain jurisdictions may request notification in advance of the release of a stacked hybrid, or may request information to conduct an environmental and food safety assessment. Examples of jurisdictions that require either notification or information about stacked hybrids prior to their release into the environment, and for use in human food and livestock feed are Canada and Japan.

The stacked hybrid GA21 X MON810 expresses two novel proteins: a modified EPSPS protein which confers tolerance to the herbicide glyphosate, and the delta-endotoxin Cry1Ab which confers resistance to the European Corn Borer and other lepidopterans, The modified EPSPS protein is produced by the mepsps gene from GA21, and the insecticidal protein Cry1Ab is produced by the cry1Ab from MON810. The novel traits of each parental line have been combined, through traditional plant breeding, to produce this new hybrid. For a full description of each parental line please refer to the individual product descriptions in the crop database for GA21 and MON810.
The inserted genes and their gene products have a history of safe use, and have undergone review and approval by several regulatory agencies. No interactions among the gene products or negative synergistic effects are expected in the stacked hybrid. The Cry1Ab protein is not an enzyme and therefore does not affect plant metabolism. The modified EPSPS has high affinity for its substrates phosphoenolpyruvate (PEP) and shikimate-3-phosphate, which are part of the shikimate metabolic pathway. EPSPS and Cry1Ab are therefore not expected to interact within, nor affect the metabolism of the stacked hybrid.
Heterosis is expected in F1 hybrids. An example of heterosis is a substantial increase in yield in the F1 hybrid compared to the parental lines. The stacked hybrid GA21 X MON810 is therefore expected to display heterosis, as would any conventional F1 hybrid. Heterosis in this hybrid is not expected to be caused by the introduced genes, since the gene products are not expected to interact synergistically.