Nowadays, the genomes of various organisms, from single celled microbes to multicellular plants and animals, can be purposely transformed using recombinant DNA technology. GMOs are used mainly in the production of pharmaceuticals, gene therapy, and agriculture. However, there are ethical issues concerning their use and production. No matter how crucial their uses are, the limitation of the knowledge of modern science as well as the possibility of unforeseen negative effects in the health and the environment are some of the issues being raised up against their use.
See also: recombinant DNA technology.