What is genetic engineering characterized by?

Genetic engineering is the artificial manipulation, modification, and recombination of DNA or other nucleic acid molecules to modify an organism or population of organisms.

Much of recombinant DNA technology involves the introduction of foreign genes into plasmids of common laboratory bacterial strains. Thus, by incorporating foreign DNA (such as a mammalian gene) into a bacterium, researchers can obtain an almost unlimited number of copies of the inserted gene. In addition, if the introduced gene is active, the modified bacterium will produce a protein designated foreign DNA.