How did American genetically modified soybeans come into being?

In 1980s, researchers from Monsanto Company in the United States cloned the resistance gene (EPsPs gene) from Petunia, and used plasmid-mediated DNA transfer technology to control the 35s promoter in Petunia plasmid (caMv) and introduced the EPsPs gene into soybean genome, thus cultivating glyphosate-resistant soybean varieties. Genetically modified soybeans can resist the herbicide glyphosate (poison drop mixture). Glyphosate kills common soybean plants and weeds. This kind of soybean is called transgenic soybean. This genetically modified soybean was approved by the US Food and Drug Administration (FDA) on 1994, and became one of the genetically modified crops commercialized on a large scale earlier. Glyphosate-resistant transgenic soybeans are highly tolerant to non-selective herbicide Rwndup. The application of glyphosate herbicide in the field will not affect soybean yield. In addition, there are other types of genetically modified soybeans, such as high methionine soybean varieties, but the toxicity and safety hazards of genetically modified soybeans have always been controversial.