How is genetic engineering done?
Genetic engineering, also called transformation, works by physically removing a gene from one organism and inserting it into another, giving it the ability to express the trait encoded by that gene. It is like taking a single recipe out of a cookbook and placing it into another cookbook.
The process: Once a goal is in mind…
1) First, find an organism that naturally contains the desired trait.
2) The DNA is extracted from that organism. This is like taking out the entire cookbook.
3) The one desired gene (recipe) must be located and copied from thousands of genes that were extracted. This is called gene cloning.
4) The gene may be modified slightly to work in a more desirable way once inside the recipient organism.
5) The new gene(s), called a transgene is delivered into cells of the recipient organism. This is called transformation. The most common transformation technique uses a bacteria that naturally genetically engineer plants with its own DNA. The transgene is inserted into the bacteria, which then delivers it into cells of the organism being engineered. Another technique, called the gene gun method, shoots microscopic gold particles coated with copies of the transgene into cells of the recipient organism. With either technique, genetic engineers have no control over where or if the transgene inserts into the genome. As a result, it takes hundreds of attempts to achieve just a few transgenic organisms.
6) Once a transgenic organism has been created, traditional breeding is used to improve the characteristics of the final product. So genetic engineering does not eliminate the need for traditional breeding. It is simply a way to add new traits to the pool.