A genetically modified organism (GMO) is any organism whose genetic material has been altered using genetic engineering techniques (i.e. genetically engineered organism). GMOs are the source of medicines and genetically modified foods and are also widely used in scientific research and to produce other goods.The term GMO is very close to the technical legal term, ‘living modified organism’, defined in the Cartagena Protocol on Biosafety, which regulates international trade in living GMOs (specifically, “any living organism that possesses a novel combination of genetic material obtained through the use of modern biotechnology”).
A more specifically defined type of GMO is a “Transgenic Organism”. This is an organism whose genetic makeup has been altered by the addition of genetic material from another, unrelated organism. This should not be confused with the more general way in which “GMO” is used to classify genetically altered organisms, as typically GMOs are organisms whose genetic makeup has been altered without the addition of genetic material from an unrelated organism.
The first genetically modified mouse was in 1973 and the first plant was produced in 1983.
Genetic modification involves the mutation, insertion, or deletion of genes. Inserted genes usually come from a different species in a form of horizontal gene-transfer. In nature this can occur when exogenous DNA penetrates the cell membrane for any reason. This can be accomplished artificially by:
attaching the genes to a virus.
physically inserting the extra DNA into the nucleus of the intended host with a very small syringe.
using electroporation (that is, introducing DNA from one organism into the cell of another by use of an electric pulse).
firing small particles from a gene gun.
Other methods exploit natural forms of gene transfer, such as the ability of Agrobacterium to transfer genetic material to plants, or the ability of lentiviruses to transfer genes to animal cells.
GMOs are used in biological and medical research, production of pharmaceutical drugs, experimental medicine (e.g. gene therapy), and agriculture (e.g. golden rice, resistance to herbicides). The term “genetically modified organism” does not always imply, but can include, targeted insertions of genes from one species into another. For example, a gene from a jellyfish, encoding a fluorescent protein called GFP, or green fluorescent protein, can be physically linked and thus co-expressed with mammalian genes to identify the location of the protein encoded by the GFP-tagged gene in the mammalian cell. Such methods are useful tools for biologists in many areas of research, including those who study the mechanisms of human and other diseases or fundamental biological processes in eukaryotic or prokaryotic cells.
Bacteria were the first organisms to be modified in the laboratory, due to the relative ease of modifying their genetics.
They continue to be important model organisms for experiments in genetic engineering. In the field of synthetic biology, they have been used to test various synthetic approaches, from synthesizing genomes to creating novel nucleotides.
These organisms are now used for several purposes, and are particularly important in producing large amounts of pure human proteins for use in medicine.
Genetically modified bacteria are used to produce the protein insulin to treat diabetes. Similar bacteria have been used to produce biofuels, clotting factors to treat haemophilia, and human growth hormone to treat various forms of dwarfism.
In addition, various genetically engineered micro-organisms are routinely used as sources of enzymes for the manufacture of a variety of processed foods. These include alpha-amylase from bacteria, which converts starch to simple sugars, chymosin from bacteria or fungi, which clots milk protein for cheese making, and pectinesterase from fungi, which improves fruit juice clarity.
See also: Genetically modified food controversies
There is controversy over GMOs, especially with regard to their use in producing food. The dispute involves buyers, biotechnology companies, governmental regulators, non-governmental organizations, and scientists. The key areas of controversy related to GMO food are whether GM food should be labeled, the role of government regulators, the effect of GM crops on health and the environment, the effect on pesticide resistance, the impact of GM crops for farmers, and the role of GM crops in feeding the world population. In 2014, sales of products which had been labeled as non-GMO grew 30 percent to $1.1 billion.
There is a general scientific agreement that food from genetically modified crops is not inherently riskier to human health than conventional food, but should be tested on a case-by-case basis. No reports of ill effects have been proven in the human population from ingesting GM food. Although labeling of GMO products in the marketplace is required in many countries, it is not required in the United States and no distinction between marketed GMO and non-GMO foods is recognized by the US FDA. In a May 2014 article in The Economist it was argued that, while GM foods could potentially help feed 842 million malnourished people globally, laws such as those being considered by Vermont’s governor, Peter Shumlin, to require labeling of foods containing genetically modified ingredients, could have the unintended consequence of interrupting the process of spreading GM technologies to impoverished countries that suffer with food security problems.
The Organic Consumers Association, and the Union of Concerned Scientists, and Greenpeace stated that risks have not been adequately identified and managed, and they have questioned the objectivity of regulatory authorities. Some health groups say there are unanswered questions regarding the potential long-term impact on human health from food derived from GMOs, and propose mandatory labeling or a moratorium on such products. Concerns include contamination of the non-genetically modified food supply, effects of GMOs on the environment and nature, the rigor of the regulatory process, and consolidation of control of the food supply in companies that make and sell GMOs, or concerns over the use of herbicides with glyphosate.