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All forms of genetic modification (GM) take one or more genes from one species and introduce it into the DNA of another in order to create a “transgenic” organism with different characteristics. So, for example, a plant may be made more resistant to disease, drought or pesticides by introducing a foreign gene from another species into its genome. One of the first GM plants was created at the University of California in 1986. Here, some tobacco plants were transgenically altered with a gene from a firefly to make them bioluminescent. The result was GM tobacco capable of emitting a glow. The first commercial GM plant was the Flavr Savr tomato. Created by Calgene, this was licensed for human consumption in 1994. Specifically, Calgene used “gene silencing” technology to shut down the gene that causes tomatoes to rot, so allowing the GM produce to stay firm for longer after harvest.
所有形式的转基因都是从一种物种里取走一个或者多个基因，然后放入另一物种的遗传物质中去，这样就 可以创造出一种具有特性的转基因生物体。举个例子，如果把另一物种的基因放入一物种的基因组中去， 那么该植物品种就可能具有了抗病，抗旱，抗杀虫剂的能力。世界上第一组转基因植物于1986年由加利福 利亚大学培育出来。这些烟草接受了一只萤火虫的基因，基因发生了改变，从而具有生物发光的能力。此 次试验的结果是烟草可以发光。世界上第一批商业转基因植物是莎弗番茄，由卡尔京培育出来，并于1994 年获准上市销售。值得一提的是，卡尔京采用了基因沉默技术消除了番茄中的腐烂基因，所以这种转基因 番茄收获后能存放更久。