The GMO Panel (EFSA, 2018) assessed Maize Bt11 x MIR162 x 1507 x GA21, which is derived from crossing four genetically engineered maize events. The maize produces six additional proteins:
- Bt 11 produces the insecticidal protein Cry1Ab and is resistant to glufosinate,
- MIR162 produces the insecticidal protein Vip3Aa20 and the phosphomannose isomerase (PMI) protein (used as a selectable marker),
- 1507 produces the insecticidal protein Cr1F and is resistant to the herbicide glufosinate,
- GA 21 is resistant to glyphosate.
Consequently, the stacked maize produces three insecticidal toxins (Cry1F, Vip3Aa20 and Cry1Ab) that target lepidoptera insects. Further, it has been engineered to be resistant to applications of glyphosate and glufosinate, with the resistance to glufosinate based on a pair of enzymes. The pairwise enzymes are likely to confer high tolerance to the spraying of the weed killers onto the maize.
EFSA (2018a) also declared three subcombinations of the plants to be safe even though they had not been assessed and without requesting experimental data: Bt11 x MIR162 x1507, MIR162 x 1507 x GA21 and MIR162 x 1507. In a minority opinion, a member of the EFSA GMO panel voiced reservations about the assessment of the subcombinations without any specific data. Amongst others, the minority opinion mentions risks for the immune system which should be thoroughly assessed.