MON 810

The MON 810 corn is a genetically modified maize used around the world. It is a Zea mays line known as YieldGard from the company Monsanto. This plant is a genetically modified organism (GMO) designed to combat crop loss due to insects. There is an inserted gene in the DNA of MON 810 which allows the plant to make a protein that harms insects that try to eat it. The inserted gene is from the Bacillus thuringiensis which produces the Bt protein that is poisonous to insects in the order Lepidoptera (butterflies and moths), including the European corn borer. These genetically modified plants with Bt protein are grown on a large scale around the world. Monsanto’s corn line MON 810 is produced by ballistically transforming another corn line with a plasmid, PV-ZMCT10. This plasmid has a cauliflower mosaic virus 35S promoter and hsp70 maize intron sequences which drive the expression of the Cry1Ab gene. The gene then codes for delta endotoxins (Cry proteins) which are toxins that are very potent and provoke lesions in the cell membrane causing cell death. These produced Bt proteins bind to certain localized sites on the epithelium of the midgut of insects. Proteins need specific receptors on cells in order to form the Cry proteins and become toxic, which is why the toxins are specific for the order Lepidoptera. The receptors are important for binding the toxic protein and starting the signal cascade, but the exact mechanism of these toxins is not well understood. MON 810’s transgene structure differs from the original plasmid constructed for the safety assessment for Monsanto and has changed compared to the naturally occurring (non-active) Cry1Ab protein. Gilles-Eric Seralini and colleagues (2007 & 2009) re-analyzed Monsanto data for MON 810 (which was made available following a demand for public availability of the data, and a court case) and claimed that it had caused liver, kidney, and heart damage in rats. However, the European Food Safety Authority (EFSA) reviewed this re-analysis and concluded that the differences observed were within a normal range for control rats and deemed the statistical methods used inappropriate.