How does the technology work?

Scientists have developed a number of techniques for getting a desired gene into a plant. One technique makes use of a soil bacterium, Agrobacterium tumefaciens. This microbe, dubbed the "first genetic engineer", has evolved the ability to insert stretches of DNA into plants. The bacterium does this to make plants produce the particular chemicals it needs to survive. Scientists get A. tumefaciens to deliver genes of their choice. Labs also use a technique called biolistics. This uses a gun to fire the desired gene into a plant's cells. The "foreign DNA" is carried on tiny pieces of gold. With luck, the plant will take up the DNA and start to read out its instructions. Wheat and rice have been modified in this way. Another method relies on protoplasts. These are plant cells which have had their tough walls removed. This gives the foreign DNA easier access to the cell interior. All these techniques depend on the remarkable fact that many plants can be regenerated from single cells or small pieces of plant tissue - as all gardeners who take cuttings know. This means a successful modification can be multiplied very quickly.