Genetic engineering is the name given to the process in which scientists move genes from one living thing to another. In this way the living thing can be made to have characteristics that it does not normally have.
The technique called gene-splicing, in which foreign genes are inserted into bacteria, was invented in 1973 by two United States scientists, Stanley Cohen and Herbert Boyer. Using gene-splicing, genetically engineered bacteria can be used to make the hormone insulin, which is used to treat the disease diabetes. Now, though, many genes have been engineered in experiments, including hundreds of human ones.
