24 Genetically modified organisms

A genetically modified organism (GMO) is any organism whose genetic material has been altered using genetic engineering techniques. The exact definition of a genetically modified organism and what constitutes genetic engineering varies, with the most common being an organism altered in a way that "does not occur naturally by mating and/or natural recombination". A wide variety of organisms have been genetically modified (GM), from animals to plants and microorganisms. Genes have been transferred within the same species, across species, and even across kingdoms. New genes can be introduced, or endogenous genes can be enhanced, altered, or knocked out.

Artificial gene synthesis, or gene synthesis, refers to a group of methods that are used in synthetic biology to construct and assemble genes from nucleotides de novo. Unlike DNA synthesis in living cells, artificial gene synthesis does not require template DNA, allowing virtually any DNA sequence to be synthesized in the laboratory. It comprises two main steps, the first of which is solid-phase DNA synthesis, sometimes known as DNA printing. This produces oligonucleotide fragments that are generally under 200 base pairs. The second step then involves connecting these oligonucleotide fragments using various DNA assembly methods. Because artificial gene synthesis does not require template DNA, it is theoretically possible to make a completely synthetic DNA molecules with no limits on the nucleotide sequence or size.

A blue rose is a flower of the genus Rosa that presents blue-to-violet pigmentation instead of the more common red, white, or yellow. Blue roses are often used to symbolize mystery or attaining the impossible. However, because of genetic limitations, they do not exist in nature. In 2004, researchers used genetic modification to create roses that contain the blue pigment delphinidin.

Gene targeting is a genetic technique that uses homologous recombination to modify an endogenous gene. The method can be used to delete a gene, remove exons, add a gene and modify individual base pairs. Gene targeting can be permanent or conditional. Conditions can be a specific time during development / life of the organism or limitation to a specific tissue, for example. Gene targeting requires the creation of a specific vector for each gene of interest. However, it can be used for any gene, regardless of transcriptional activity or gene size.

Genetically modified animals are animals that have been genetically modified for a variety of purposes including producing drugs, enhancing yields, increasing resistance to disease, etc. The vast majority of genetically modified animals are at the research stage while the number close to entering the market remains small.

Genetically modified bacteria were the first organisms to be modified in the laboratory, due to their simple genetics. 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 fish are organisms from the taxonomic clade which includes the classes Agnatha, Chondrichthyes and Osteichthyes whose genetic material (DNA) has been altered using genetic engineering techniques. In most cases, the aim is to introduce a new trait to the fish which does not occur naturally in the species, i.e. transgenesis.

A genetically modified (GM) insect is an insect that has been genetically modified, either through mutagenesis, or more precise processes of transgenesis, or cisgenesis. Motivations for using GM insects include biological research purposes and genetic pest management. Genetic pest management capitalizes on recent advances in biotechnology and the growing repertoire of sequenced genomes in order to control pest populations, including insects. Insect genomes can be found in genetic databases such as NCBI, and databases more specific to insects such as FlyBase, VectorBase, and BeetleBase. There is an ongoing initiative started in 2011 to sequence the genomes of 5,000 insects and other arthropods called the i5k. Some Lepidoptera have been genetically modified in nature by the wasp bracovirus.

Genetically modified mammals are mammals that have been genetically engineered. They are an important category of genetically modified organisms. The majority of research involving genetically modified mammals involves mice with attempts to produce knockout animals in other mammalian species limited by the inability to derive and stably culture embryonic stem cells.

A genetically modified tree is a tree whose DNA has been modified using genetic engineering techniques. In most cases the aim is to introduce a novel trait to the plant which does not occur naturally within the species. Examples include resistance to certain pests, diseases, environmental conditions, and herbicide tolerance, or the alteration of lignin levels in order to reduce pulping costs.

A genetically modified virus is a virus that has been altered or generated using biotechnology methods, and remains capable of infection. Genetic modification involves the directed insertion, deletion, artificial synthesis or change of nucleotide bases in viral genomes. Genetically modified viruses are mostly generated by the insertion of foreign genes intro viral genomes for the purposes of biomedical, agricultural, bio-control, or technological objectives. The terms genetically modified virus and genetically engineered virus are used synonymously.

The GloFish is a patented and trademarked brand of genetically engineered fluorescent fish. A variety of different GloFish are currently on the market. Zebrafish were the first GloFish available in pet stores, and are now sold in bright red, green, orange-yellow, blue, pink, and purple fluorescent colors. Recently "Electric Green", "Sunburst Orange", "Moonrise Pink", "Starfire Red", "Cosmic Blue", and "Galactic Purple" colored tetra, an "Electric Green" tiger barb and a glo-Rainbow Shark have been added to the lineup. Although not originally developed for the ornamental fish trade, it is one of the first genetically modified animals to become publicly available. The rights to GloFish are owned by Spectrum Brands, Inc., which purchased GloFish from Yorktown Technologies, the original developer of GloFish, in May 2017.

GMO conspiracy theories are conspiracy theories related to the production and sale of genetically modified crops and genetically modified food. These conspiracy theories include claims that agribusinesses, especially Monsanto, have suppressed data showing that GMOs cause harm, deliberately cause food shortages to promote the use of GM food, or have co-opted government agencies such as the United States Food and Drug Administration or scientific societies such as the American Association for the Advancement of Science. Critics charge that GMO conspiracy theories are largely promulgated by those opposing the production and sale of GMOs, and instances of unsubstantiated conspiracy theories have lately occurred in the context of public health issues that are mostly unrelated to GMOs, including the 2015–16 Zika virus outbreak and concerns over food safety at Chipotle Mexican Grill.

Hachimoji DNA is a synthetic nucleic acid analog that uses four synthetic nucleotides in addition to the four present in the natural nucleic acids, DNA and RNA. This leads to four allowed base pairs: two unnatural base pairs formed by the synthetic nucleobases in addition to the two normal pairs. Hachimoji bases have been demonstrated in both DNA and RNA analogs, using deoxyribose and ribose respectively as the backbone sugar.

The International Mouse Phenotyping Consortium (IMPC) is an international scientific endeavour to create and characterize the phenotype of 20,000 knockout mouse strains. Launched in September 2011, the consortium consists of over 15 research institutes across four continents with funding provided by the NIH, European national governments and the partner institutions.

A knockout moss is a moss plant in which one or more specific genes are deleted or inactivated by gene targeting. After deletion of a gene, the knockout moss has lost the trait encoded by this gene. Thus, the function of this gene can be inferred. This scientific approach is called reverse genetics as the scientist wants to unravel the function of a specific gene. In classical genetics the scientist starts with a phenotype of interest and searches for the gene that causes this phenotype. Knockout mosses are relevant for basic research in biology as well as in biotechnology.

A knockout rat is a genetically engineered rat with a single gene turned off through a targeted mutation used for academic and pharmaceutical research. Knockout rats can mimic human diseases and are important tools for studying gene function and for drug discovery and development. The production of knockout rats was not economically or technically feasible until 2008.

Mendocino County, California, was the first jurisdiction in the United States to ban the cultivation, production or distribution of genetically modified organisms (GMOs). The ordinance, entitled Measure H, was passed by referendum on March 2, 2004. Initiated by the group "GMO Free Mendocino", the campaign was a highly publicized grassroots effort by local farmers and environmental groups who contend that the potential risks of GMOs to human health and the ecosystem have not yet been fully understood. The measure was met with opposition by several interest groups representing the biotechnology industry, The California Plant Health Association and CropLife America, a Washington-based consortium whose clients represent some of the largest food distributors in the nation, including Monsanto, DuPont and Dow Chemical. Since the enactment of the ordinance, Mendocino County has been added to an international list of "GMO free zones." Pre-emptive statutes banning local municipalities from such ordinances have now become widespread with adoption in sixteen states.

In molecular biology, mutagenesis is an important laboratory technique whereby DNA mutations are deliberately engineered to produce libraries of mutant genes, proteins, strains of bacteria, or other genetically modified organisms. The various constituents of a gene, as well as its regulatory elements and its gene products, may be mutated so that the functioning of a genetic locus, process, or product can be examined in detail. The mutation may produce mutant proteins with interesting properties or enhanced or novel functions that may be of commercial use. Mutant strains may also be produced that have practical application or allow the molecular basis of a particular cell function to be investigated.

The pGLO plasmid is an engineered plasmid used in biotechnology as a vector for creating genetically modified organisms. The plasmid contains several reporter genes, most notably the green fluorescent protein (GFP) and the ampicillin resistance gene. GFP was isolated from the jelly fish Aequorea victoria. Because it shares a bidirectional promoter with a gene for metabolizing arabinose, the GFP gene is expressed in the presence of arabinose, which makes the transgenic organism express its fluorescence under UV light. GFP can be induced in bacteria containing the pGLO plasmid by growing them on +arabinose plates. pGLO is made by Bio-Rad Laboratories.

The Pusztai affair is a controversy that began in 1998. Protein scientist Árpád Pusztai went public with the initial results of unpublished research he was conducting at the Rowett Institute in Aberdeen, Scotland, investigating the possible effects of genetically modified potatoes upon rats. Pusztai claimed that the genetically modified potatoes had stunted growth and repressed the rats' immune systems while thickening their gut mucosa. Initially supported by the Rowett Institute, his comments on a British television programme caused a storm of controversy, and the Rowett Institute withdrew its support. Pusztai was suspended and misconduct procedures were used to seize his data and ban him from speaking publicly. The institute did not renew his annual contract and Pusztai was criticized by the British Royal Society and some other scientists for making an announcement before his experiment was complete or peer-reviewed and for the experiment's design, methodology and analysis. Some of the data from the study was eventually published in The Lancet in 1999 after five out of six peer reviewers approved of the study – triggering further controversy.

Science Moms is a 2017 American documentary film about mothers who advocate for science-based decision-making concerning the health and nutrition of children. The film covers vaccines, autism, celebrity-endorsed health fads, cancer, allergies, organic food, GMOs, homeopathy, and the appeal to nature fallacy.

Cnidarians such as Hydra have become attractive model organisms to study the evolution of immunity. However, despite long-term efforts, stably transgenic animals could not be generated, severely limiting the functional analysis of genes. For analytical purposes, therefore, an important technical breakthrough in the field was the development of a transgenic procedure for generation of stably transgenic lines by embryo microinjection.