Editing Genetic engineering (section)

== Applications ==

Genetic engineering has applications in medicine, research, industry and agriculture and can be used on a wide range of plants, animals and microorganisms. [[Bacteria]], the first organisms to be genetically modified, can have plasmid DNA inserted containing new genes that code for medicines or enzymes that process food and other [[Enzyme substrate (biology)|substrates]].<ref>{{cite web|url=http://www.learner.org/courses/biology/textbook/gmo/gmo_2.html|title=Genetic Modification of Bacteria|publisher=[[Annenberg Foundation]]|access-date=4 October 2012|archive-date=24 December 2013|archive-url=https://web.archive.org/web/20131224110848/http://www.learner.org/courses/biology/textbook/gmo/gmo_2.html}}</ref><ref>Panesar, Pamit et al. (2010) "Enzymes in Food Processing: Fundamentals and Potential Applications", Chapter 10, I K International Publishing House, {{ISBN|978-93-80026-33-6}}</ref> Plants have been modified for insect protection, [[herbicide resistance]], virus resistance, enhanced nutrition, tolerance to environmental pressures and the production of [[edible vaccines]].<ref>{{cite web|url=http://www.isaaa.org/gmapprovaldatabase/gmtraitslist/default.asp|title=GM traits list|publisher=International Service for the Acquisition of Agri-Biotech Applications}}</ref> Most commercialised GMOs are insect resistant or herbicide tolerant crop plants.<ref>{{cite web|url=http://www.isaaa.org/resources/publications/briefs/43/executivesummary/default.asp|title=ISAAA Brief 43-2011: Executive Summary|publisher=International Service for the Acquisition of Agri-Biotech Applications}}</ref> Genetically modified animals have been used for research, model animals and the production of agricultural or pharmaceutical products. The genetically modified animals include animals with [[knock-out mice|genes knocked out]], [[oncomouse|increased susceptibility to disease]], hormones for extra growth and the ability to express proteins in their milk.<ref>{{cite news|url=https://www.independent.co.uk/news/science/the-mouse-that-shook-the-world-744870.html|title=The mouse that shook the world|last=Connor|first=Steve| name-list-style = vanc |date=2 November 2007|newspaper=The Independent}}</ref>

=== Medicine ===

Genetic engineering has many applications to medicine that include the manufacturing of drugs, creation of [[Model organism|model animals]] that mimic human conditions and [[gene therapy]]. One of the earliest uses of genetic engineering was to mass-produce human insulin in bacteria.<ref name="GoeddelKleidBolivarHeynekerYansuraCreaHiroseKraszewskiItakuraRiggs1979" /> This application has now been applied to human [[growth hormone]]s, [[Follicle-stimulating hormone|follicle stimulating hormones]] (for treating infertility), [[Albumin human|human albumin]], [[monoclonal antibodies]], [[antihemophilic factor]]s, [[vaccine]]s and many other drugs.<ref>{{cite book|url={{google books |plainurl=y |id=gR8cWf2-UY4C}}|title=The hope, hype & reality of genetic engineering: remarkable stories from agriculture, industry, medicine, and the environment|last=Avise|first=John C.| name-list-style = vanc |publisher=Oxford University Press US|year=2004|isbn=978-0-19-516950-8|page=22}}</ref><ref>{{cite news|date=10 December 2012|title=Engineering algae to make complex anti-cancer 'designer' drug|url=http://phys.org/news/2012-12-algae-complex-anti-cancer-drug.html|work=PhysOrg|access-date=15 April 2013}}</ref> Mouse [[Hybridoma technology|hybridomas]], cells fused together to create [[monoclonal antibodies]], have been adapted through genetic engineering to create human monoclonal antibodies.<ref>{{cite journal | vauthors = Roque AC, Lowe CR, Taipa MA | title = Antibodies and genetically engineered related molecules: production and purification | journal = Biotechnology Progress | volume = 20 | issue = 3 | pages = 639–54 | year = 2004 | pmid = 15176864 | doi = 10.1021/bp030070k | s2cid = 23142893 }}</ref> [[Genetically engineered virus]]es are being developed that can still confer immunity, but lack the [[Infectious Disease|infectious]] [[DNA sequence|sequences]].<ref>{{cite journal | vauthors = Rodriguez LL, Grubman MJ | title = Foot and mouth disease virus vaccines | journal = Vaccine | volume = 27 | pages = D90-4 | date = November 2009 | issue = Suppl 4 | pmid = 19837296 | doi = 10.1016/j.vaccine.2009.08.039 }}</ref>

Genetic engineering is also used to create animal models of human diseases. [[Genetically modified mouse|Genetically modified mice]] are the most common genetically engineered animal model.<ref>{{cite web|url=http://www.geneticsandsociety.org/article.php?id=386|title=Background: Cloned and Genetically Modified Animals|date=14 April 2005|publisher=Center for Genetics and Society|access-date=9 July 2010|archive-url=https://web.archive.org/web/20161123110939/http://geneticsandsociety.org/article.php?id=386|archive-date=23 November 2016}}</ref> They have been used to study and model cancer (the [[oncomouse]]), obesity, heart disease, diabetes, arthritis, substance abuse, anxiety, aging and Parkinson disease.<ref>{{cite web|url=http://www.genome.gov/12514551|title=Knockout Mice|year=2009|publisher=Nation Human Genome Research Institute}}</ref> Potential cures can be tested against these mouse models. 

Gene therapy is the [[Human genetic engineering|genetic engineering of humans]], generally by replacing defective genes with effective ones. [[Clinical research]] using [[Somatic (biology)|somatic]] gene therapy has been conducted with several diseases, including [[X-linked severe combined immunodeficiency|X-linked SCID]],<ref>{{cite journal | vauthors = Fischer A, Hacein-Bey-Abina S, Cavazzana-Calvo M | title = 20 years of gene therapy for SCID | journal = Nature Immunology | volume = 11 | issue = 6 | pages = 457–60 | date = June 2010 | pmid = 20485269 | doi = 10.1038/ni0610-457 | s2cid = 11300348 }}</ref> [[chronic lymphocytic leukemia]] (CLL),<ref name="Porter">{{cite journal |doi=10.1038/news.2011.472 |title=Cell therapy fights leukaemia |year=2011 |last1=Ledford |first1=Heidi | name-list-style = vanc |journal=Nature }}</ref><ref>{{cite journal | vauthors = Brentjens RJ, Davila ML, Riviere I, Park J, Wang X, Cowell LG, Bartido S, Stefanski J, Taylor C, Olszewska M, Borquez-Ojeda O, Qu J, Wasielewska T, He Q, Bernal Y, Rijo IV, Hedvat C, Kobos R, Curran K, Steinherz P, Jurcic J, Rosenblat T, Maslak P, Frattini M, Sadelain M | display-authors = 6 | title = CD19-targeted T cells rapidly induce molecular remissions in adults with chemotherapy-refractory acute lymphoblastic leukemia | journal = Science Translational Medicine | volume = 5 | issue = 177 | pages = 177ra38 | date = March 2013 | pmid = 23515080 | pmc = 3742551 | doi = 10.1126/scitranslmed.3005930 }}</ref> and [[Parkinson's disease]].<ref>{{cite journal | vauthors = LeWitt PA, Rezai AR, Leehey MA, Ojemann SG, Flaherty AW, Eskandar EN, Kostyk SK, Thomas K, Sarkar A, Siddiqui MS, Tatter SB, Schwalb JM, Poston KL, Henderson JM, Kurlan RM, Richard IH, Van Meter L, Sapan CV, During MJ, Kaplitt MG, Feigin A | display-authors = 6 | title = AAV2-GAD gene therapy for advanced Parkinson's disease: a double-blind, sham-surgery controlled, randomised trial | journal = The Lancet. Neurology | volume = 10 | issue = 4 | pages = 309–19 | date = April 2011 | pmid = 21419704 | doi = 10.1016/S1474-4422(11)70039-4 | s2cid = 37154043 }}</ref> In 2012, [[Alipogene tiparvovec]] became the first gene therapy treatment to be approved for clinical use.<ref name="Gallagher">{{Cite news|date=2012-11-02|title=Gene therapy: Glybera approved by European Commission|language=en-GB|work=BBC News|url=https://www.bbc.com/news/health-20179561|access-date=2023-03-30}}</ref><ref name="Richards2012">{{cite web|last=Richards|first=Sabrina| name-list-style = vanc |title=Gene Therapy Arrives in Europe|url=http://www.the-scientist.com/?articles.view/articleNo/33166/title/Gene-Therapy-Arrives-in-Europe/|publisher=The Scientist|access-date=16 November 2012}}</ref> In 2015 a virus was used to insert a healthy gene into the skin cells of a boy suffering from a rare skin disease, [[epidermolysis bullosa]], in order to grow, and then graft healthy skin onto 80 percent of the boy's body which was affected by the illness.<ref>{{Cite news|url=https://www.npr.org/2017/11/08/562647401/genetically-altered-skin-saves-a-boy-dying-of-a-rare-disease?sc=tw|title=Genetically Altered Skin Saves A Boy Dying of a Rare Disease|work=NPR.org|access-date=2017-11-15|language=en}}</ref>

[[Germline]] gene therapy would result in any change being inheritable, which has raised concerns within the scientific community.<ref>{{cite web|url=http://www.cioms.ch/frame_1990_texts_of_guidelines.htm |title=1990 The Declaration of Inuyama |date=5 August 2001 |url-status=bot: unknown |archive-url=https://web.archive.org/web/20010805085535/http://www.cioms.ch/frame_1990_texts_of_guidelines.htm |archive-date=5 August 2001 }}</ref><ref>{{cite journal | vauthors = Smith KR, Chan S, Harris J | title = Human germline genetic modification: scientific and bioethical perspectives | journal = Archives of Medical Research | volume = 43 | issue = 7 | pages = 491–513 | date = October 2012 | pmid = 23072719 | doi = 10.1016/j.arcmed.2012.09.003 }}</ref> In 2015, CRISPR was used to edit the DNA of non-viable [[human embryos]],<ref name="NYT-20150423">{{cite news |last=Kolata |first=Gina | name-list-style = vanc |title=Chinese Scientists Edit Genes of Human Embryos, Raising Concerns |url=https://www.nytimes.com/2015/04/24/health/chinese-scientists-edit-genes-of-human-embryos-raising-concerns.html |archive-url=https://ghostarchive.org/archive/20220102/https://www.nytimes.com/2015/04/24/health/chinese-scientists-edit-genes-of-human-embryos-raising-concerns.html |archive-date=2022-01-02 |url-access=limited |url-status=live |date=23 April 2015 |work=The New York Times |access-date=24 April 2015 }}{{cbignore}}</ref><ref name="PC-20150418">{{cite journal | vauthors = Liang P, Xu Y, Zhang X, Ding C, Huang R, Zhang Z, Lv J, Xie X, Chen Y, Li Y, Sun Y, Bai Y, Songyang Z, Ma W, Zhou C, Huang J | display-authors = 6 | title = CRISPR/Cas9-mediated gene editing in human tripronuclear zygotes | journal = Protein & Cell | volume = 6 | issue = 5 | pages = 363–372 | date = May 2015 | pmid = 25894090 | pmc = 4417674 | doi = 10.1007/s13238-015-0153-5 }}</ref> leading scientists of major world academies to call for a moratorium on inheritable human genome edits.<ref name="NYT-20151203-nw">{{cite news |last=Wade |first=Nicholas | name-list-style = vanc |author-link=Nicholas Wade |title=Scientists Place Moratorium on Edits to Human Genome That Could Be Inherited |url=https://www.nytimes.com/2015/12/04/science/crispr-cas9-human-genome-editing-moratorium.html |archive-url=https://ghostarchive.org/archive/20220102/https://www.nytimes.com/2015/12/04/science/crispr-cas9-human-genome-editing-moratorium.html |archive-date=2022-01-02 |url-access=limited |url-status=live |date=3 December 2015 |work=The New York Times |access-date=3 December 2015 }}{{cbignore}}</ref> There are also concerns that the technology could be used not just for treatment, but for enhancement, modification or alteration of a human beings' appearance, adaptability, intelligence, character or behavior.<ref>{{cite web|title=The Ethics of Gene Therapy|first=Emilie R. |last=Bergeson| name-list-style = vanc |year=1997|url=http://www.ndsu.edu/pubweb/~mcclean/plsc431/students/bergeson.htm}}</ref> The distinction between cure and enhancement can also be difficult to establish.<ref>{{cite web|first=Kathi E. |last=Hanna| name-list-style = vanc |url=http://www.genome.gov/10004767|publisher=National Human Genome Research Institute|title=Genetic Enhancement}}</ref> In November 2018, [[He Jiankui]] announced that he had [[Genome editing|edited the genomes]] of two human embryos, to attempt to disable the ''[[CCR5]]'' gene, which codes for a receptor that [[HIV]] uses to enter cells. The work was widely condemned as unethical, dangerous, and premature.<ref>{{cite news |last1=Begley |first1=Sharon | name-list-style = vanc |title=Amid uproar, Chinese scientist defends creating gene-edited babies – STAT |url=https://www.statnews.com/2018/11/28/chinese-scientist-defends-creating-gene-edited-babies/ |work=STAT |date=28 November 2018}}</ref> Currently, germline modification is banned in 40 countries. Scientists that do this type of research will often let embryos grow for a few days without allowing it to develop into a baby.<ref>{{cite journal |last1=Li |first1=Emily |title=Diagnostic Value of Spiral CT Chest Enhanced Scan |journal=Journal of Clinical and Nursing Research |date=July 31, 2020 |url=http://scholar.googleusercontent.com/scholar?q=cache:h6ILNa11QgIJ:scholar.google.com/+%E2%80%8BLi,+E.+(2020).+Risks+of+CRISPR+Gene+Editing+and+An+Answer+to+Them.+%E2%80%8BJournal+of+Clinical+and+Nursing+Research,%E2%80%8B+%E2%80%8B4(%E2%80%8B+4).&hl=en&as_sdt=0,21}}</ref>

Researchers are altering the genome of pigs to induce the growth of human organs, with the aim of increasing the success of [[Xenotransplantation|pig to human organ transplantation]].<ref name="Medical News Today">{{cite news|date=21 September 2003|title=GM pigs best bet for organ transplant|work=Medical News Today|url=http://www.medicalnewstoday.com/articles/4344.php|access-date=9 July 2010|archive-date=10 May 2011|archive-url=https://web.archive.org/web/20110510121726/http://www.medicalnewstoday.com/articles/4344.php}}</ref> Scientists are creating "gene drives", changing the genomes of mosquitoes to make them immune to malaria, and then looking to spread the genetically altered mosquitoes throughout the mosquito population in the hopes of eliminating the disease.<ref>{{Cite news|url=https://www.nytimes.com/2015/11/27/us/2015-11-27-us-animal-gene-editing.html |archive-url=https://ghostarchive.org/archive/20220102/https://www.nytimes.com/2015/11/27/us/2015-11-27-us-animal-gene-editing.html |archive-date=2022-01-02 |url-access=limited |url-status=live|title=Open Season Is Seen in Gene Editing of Animals|last=Harmon|first=Amy| name-list-style = vanc |date=2015-11-26|work=The New York Times|access-date=2017-09-27|language=en-US|issn=0362-4331}}{{cbignore}}</ref>

=== Research ===

[[File:PCWmice1.jpg|thumb|[[Knockout mouse|Knockout mice]]]]

[[File:Expression of Human Wild-Type and P239S Mutant Palladin.png|thumb|Human cells in which some proteins are fused with [[green fluorescent protein]] to allow them to be visualised]]

Genetic engineering is an important tool for [[natural scientists]], with the creation of transgenic organisms one of the most important tools for analysis of gene function.<ref>{{cite book | vauthors = Praitis V, Maduro MF | title = Caenorhabditis elegans: Molecular Genetics and Development | chapter = Transgenesis in C. elegans | series = Methods in Cell Biology | volume = 106 | pages = 161–85 | date = 2011 | pmid = 22118277 | doi = 10.1016/B978-0-12-544172-8.00006-2 | isbn = 978-0-12-544172-8 }}</ref> Genes and other genetic information from a wide range of organisms can be inserted into bacteria for storage and modification, creating [[genetically modified bacteria]] in the process. Bacteria are cheap, easy to grow, [[Clone (cell biology)|clonal]], multiply quickly, relatively easy to transform and can be stored at -80&nbsp;°C almost indefinitely. Once a gene is isolated it can be stored inside the bacteria providing an unlimited supply for research.<ref>{{Cite web|url=https://www.learner.org/courses/biology/textbook/gmo/gmo_2.html|title=Rediscovering Biology – Online Textbook: Unit 13 Genetically Modified Organisms|website=www.learner.org|access-date=2017-08-18|archive-date=3 December 2019|archive-url=https://web.archive.org/web/20191203123559/http://www.learner.org/courses/biology/textbook/gmo/gmo_2.html}}</ref>

Organisms are genetically engineered to discover the functions of certain genes. This could be the effect on the phenotype of the organism, where the gene is expressed or what other genes it interacts with. These experiments generally involve loss of function, gain of function, tracking and expression.

* '''Loss of function experiments''', such as in a [[gene knockout]] experiment, in which an organism is engineered to lack the activity of one or more genes. In a simple knockout a copy of the desired gene has been altered to make it non-functional. [[Embryonic stem cells]] incorporate the altered gene, which replaces the already present functional copy. These stem cells are injected into [[blastocyst]]s, which are implanted into surrogate mothers. This allows the experimenter to analyse the defects caused by this [[mutation]] and thereby determine the role of particular genes. It is used especially frequently in [[developmental biology]].<ref name="AlbertsJohnsonLewisRaffRobertsWalter2002">{{Cite book |last1=Alberts |first1=Bruce |last2=Johnson |first2=Alexander |last3=Lewis |first3=Julian |last4=Raff |first4=Martin |last5=Roberts |first5=Keith |last6=Walter |first6=Peter | name-list-style =  vanc |date=2002 |chapter=Studying Gene Expression and Function|url=https://www.ncbi.nlm.nih.gov/books/NBK26818/ |title=Molecular Biology of the Cell |edition=4th |location=New York|publisher=Garland Science |isbn=0-8153-3218-1}}</ref> When this is done by creating a library of genes with point mutations at every position in the area of interest, or even every position in the whole gene, this is called "scanning mutagenesis". The simplest method, and the first to be used, is "alanine scanning", where every position in turn is mutated to the unreactive amino acid [[alanine]].<ref>{{Cite book|url=https://books.google.com/books?id=ycVoWFqDTmAC&pg=PA94|title=Protein Engineering and Design|last1=Park|first1=Sheldon J.|last2=Cochran|first2=Jennifer R.| name-list-style = vanc |date=2009-09-25|publisher=CRC Press|isbn=978-1-4200-7659-2|language=en}}</ref>
* '''Gain of function experiments''', the logical counterpart of knockouts. These are sometimes performed in conjunction with knockout experiments to more finely establish the function of the desired gene. The process is much the same as that in knockout engineering, except that the construct is designed to increase the function of the gene, usually by providing extra copies of the gene or inducing synthesis of the protein more frequently. Gain of function is used to tell whether or not a protein is sufficient for a function, but does not always mean it is required, especially when dealing with genetic or functional redundancy.<ref name="AlbertsJohnsonLewisRaffRobertsWalter2002" />
* '''Tracking experiments''', which seek to gain information about the localisation and interaction of the desired protein. One way to do this is to replace the wild-type gene with a 'fusion' gene, which is a juxtaposition of the wild-type gene with a reporting element such as [[green fluorescent protein]] (GFP) that will allow easy visualisation of the products of the genetic modification. While this is a useful technique, the manipulation can destroy the function of the gene, creating secondary effects and possibly calling into question the results of the experiment. More sophisticated techniques are now in development that can track protein products without mitigating their function, such as the addition of small sequences that will serve as binding motifs to monoclonal antibodies.<ref name="AlbertsJohnsonLewisRaffRobertsWalter2002" />
* '''Expression studies''' aim to discover where and when specific proteins are produced. In these experiments, the DNA sequence before the DNA that codes for a protein, known as a gene's [[promoter (biology)|promoter]], is reintroduced into an organism with the protein coding region replaced by a reporter gene such as GFP or an enzyme that catalyses the production of a dye. Thus the time and place where a particular protein is produced can be observed. Expression studies can be taken a step further by altering the promoter to find which pieces are crucial for the proper expression of the gene and are actually bound by transcription factor proteins; this process is known as [[promoter bashing]].<ref>{{Cite book|url=https://books.google.com/books?id=ed4_CQAAQBAJ&pg=PA114 |title=Techniques in Genetic Engineering|last=Kurnaz|first=Isil Aksan| name-list-style = vanc |date=2015-05-08|publisher=CRC Press|isbn=978-1-4822-6090-8 }}</ref>

=== Industrial ===
{{Main|Industrial microbiology}}Organisms can have their cells transformed with a gene coding for a useful protein, such as an enzyme, so that they will [[Protein expression (biotechnology)|overexpress]] the desired protein. Mass quantities of the protein can then be manufactured by growing the transformed organism in [[bioreactor]] equipment using [[industrial fermentation]], and then [[Protein purification|purifying]] the protein.<ref>{{cite web|title=Applications of Genetic Engineering |publisher=Microbiologyprocedure |url=http://www.microbiologyprocedure.com/microbial-genetics/applications-of-genetic-engineering.htm |access-date=9 July 2010 |archive-url=https://web.archive.org/web/20110714085807/http://www.microbiologyprocedure.com/microbial-genetics/applications-of-genetic-engineering.htm |archive-date=14 July 2011 }}</ref> Some genes do not work well in bacteria, so yeast, insect cells or mammalian cells can also be used.<ref>{{cite web|title=Biotech: What are transgenic organisms? |publisher=Easyscience |year=2002 |url=http://www.easyscience.co.nz/ubbiology/biotech/lesson4.htm |access-date=9 July 2010 |archive-url=https://web.archive.org/web/20100527060202/http://www.easyscience.co.nz/ubbiology/biotech/lesson4.htm |archive-date=27 May 2010 }}</ref> These techniques are used to produce medicines such as [[insulin]], [[human growth hormone]], and [[vaccine]]s, supplements such as [[tryptophan]], aid in the production of food ([[chymosin]] in cheese making) and fuels.<ref>{{cite magazine|title=Making Gasoline from Bacteria: A biotech startup wants to coax fuels from engineered microbes|first=Neil|last=Savage|name-list-style=vanc|date=1 August 2007|url=http://www.technologyreview.com/biztech/19128/|magazine=[[MIT Technology Review]]|access-date=16 July 2015|archive-date=9 April 2020|archive-url=https://web.archive.org/web/20200409015344/https://www.technologyreview.com/biztech/19128/}}</ref> Other applications with genetically engineered bacteria could involve making them perform tasks outside their natural cycle, such as making [[biofuel]]s,<ref>{{cite web | last = Summers | first = Rebecca | name-list-style = vanc | date = 24 April 2013 | url = https://www.newscientist.com/article/dn23431-bacteria-churn-out-first-ever-petrollike-biofuel.html | title = Bacteria churn out first ever petrol-like biofuel | work = New Scientist | access-date = 27 April 2013 }}</ref> cleaning up oil spills, carbon and other toxic waste<ref>{{cite web|title=Applications of Some Genetically Engineered Bacteria |url=http://www.molecular-plant-biotechnology.info/use-of-microbes-in-industry-and-agriculture/applications-of-genetically-engineered-bacteria.htm |access-date=9 July 2010 |archive-url=https://web.archive.org/web/20101127053814/http://molecular-plant-biotechnology.info/use-of-microbes-in-industry-and-agriculture/applications-of-genetically-engineered-bacteria.htm |archive-date=27 November 2010 }}</ref> and detecting arsenic in drinking water.<ref>{{cite web | last = Sanderson | first = Katherine | name-list-style = vanc | date = 24 February 2012 | url = http://cen.acs.org/articles/90/web/2012/02/New-Portable-Kit-Detects-Arsenic.html | title = New Portable Kit Detects Arsenic in Wells | work = Chemical and Engineering News | access-date = 23 January 2013 }}</ref> Certain genetically modified microbes can also be used in [[biomining]] and [[bioremediation]], due to their ability to extract heavy metals from their environment and incorporate them into compounds that are more easily recoverable.<ref>{{Cite book|title = Campbell Biology Ninth Edition|last1 = Reece|first1 = Jane B.|first2 = Lisa A.|last2 = Urry|last3 = Cain|first3 = Michael L.|last4 = Wasserman|first4 = Steven A.|last5 = Minorsky|first5 = Peter V.|last6 = Jackson|first6 = Robert B.|name-list-style = vanc|publisher = Pearson Benjamin Cummings|year = 2011|isbn = 978-0-321-55823-7|location = San Francisco|page = [https://archive.org/details/campbellbiologyj00reec/page/421 421]|url = https://archive.org/details/campbellbiologyj00reec/page/421}}</ref>

In [[materials science]], a genetically modified virus has been used in a research laboratory as a scaffold for assembling a more environmentally friendly [[lithium-ion battery]].<ref>{{cite web|url=http://web.mit.edu/newsoffice/2009/virus-battery-0402.html |title= New virus-built battery could power cars, electronic devices |publisher=Web.mit.edu |date=2 April 2009 |access-date=17 July 2010}}</ref><ref>{{cite news|url=https://www.npr.org/templates/story/story.php?storyId=102647672 |title=Hidden Ingredient in New, Greener Battery: A Virus |newspaper=Npr.org |access-date=17 July 2010}}</ref> Bacteria have also been engineered to function as sensors by expressing a fluorescent protein under certain environmental conditions.<ref>{{cite web|title=Researchers Synchronize Blinking 'Genetic Clocks' – Genetically Engineered Bacteria That Keep Track of Time|website=ScienceDaily|date=24 January 2010|url=https://www.sciencedaily.com/releases/2010/01/100120131157.htm}}</ref>

===Agriculture===

{{Main|Genetically modified crops|Genetically modified food}}

[[File:Bt plants.png|thumb|upright|Bt-toxins present in [[peanut]] leaves (bottom image) protect it from extensive damage caused by [[lesser cornstalk borer]] [[larva]]e (top image).<ref>{{cite web |last=Suszkiw |first=Jan | name-list-style = vanc |url=http://ars.usda.gov/is/ar/archive/nov99/pest1199.htm |title=Tifton, Georgia: A Peanut Pest Showdown |access-date=23 November 2008 |work= [[Agricultural Research Service|Agricultural Research]] |date=November 1999}}</ref>]]

One of the best-known and [[Genetically modified food controversies|controversial]] applications of genetic engineering is the creation and use of [[genetically modified crops]] or [[genetically modified livestock]] to produce [[genetically modified food]]. Crops have been developed to increase production, increase tolerance to [[abiotic stress]]es, alter the composition of the food, or to produce novel products.<ref>{{cite journal | vauthors = Magaña-Gómez JA, de la Barca AM | title = Risk assessment of genetically modified crops for nutrition and health | journal = Nutrition Reviews | volume = 67 | issue = 1 | pages = 1–16 | date = January 2009 | pmid = 19146501 | doi = 10.1111/j.1753-4887.2008.00130.x | doi-access = free }}</ref>

The first crops to be released commercially on a large scale provided protection from insect pests or tolerance to [[herbicides]]. Fungal and virus resistant crops have also been developed or are in development.<ref>{{cite journal |doi=10.3329/ptcb.v16i2.1113 |title=Fungus Resistant Transgenic Plants: Strategies, Progress and Lessons Learnt |year=2008 |last1=Islam |first1=Aparna | name-list-style = vanc |journal=Plant Tissue Culture and Biotechnology |volume=16 |issue=2 |pages=117–38|doi-access=free }}</ref><ref>{{cite web|title=Disease resistant crops|publisher=GMO Compass|url=http://www.gmo-compass.org/eng/agri_biotechnology/breeding_aims/148.disease_resistant_crops.html|archive-url=https://web.archive.org/web/20100603215011/http://www.gmo-compass.org/eng/agri_biotechnology/breeding_aims/148.disease_resistant_crops.html|archive-date=3 June 2010}}</ref> This makes the insect and weed management of crops easier and can indirectly increase crop yield.<ref>{{cite journal |doi=10.1111/j.1744-7348.2004.tb00376.x |title=First impact of biotechnology in the EU: Bt maize adoption in Spain |year=2004 | vauthors = Demont M, Tollens E |journal=Annals of Applied Biology |volume=145 |issue=2 |pages=197–207}}</ref><ref name="Biodiversity">{{cite book |url=https://archive.org/details/sustaininglifeho00eric|title=Sustaining Life |last1=Chivian|first1=Eric|last2=Bernstein|first2=Aaron | name-list-style = vanc |publisher=Oxford University Press, Inc|year=2008|isbn=978-0-19-517509-7 |url-access=registration}}<!--|access-date=12 September 2009 --></ref> GM crops that directly improve yield by accelerating growth or making the plant more hardy (by improving salt, cold or drought tolerance) are also under development.<ref name="Deborah B. Whitman 2000" /> In 2016 [[AquAdvantage salmon|Salmon]] have been genetically modified with growth hormones to reach normal adult size much faster.<ref name="Genetically Engineered Salmon">{{cite news|url=https://www.nytimes.com/2015/11/20/business/genetically-engineered-salmon-approved-for-consumption.html?_r=0|title=Genetically Engineered Salmon Approved for Consumption|date=19 November 2015|work=The New York Times|last1=Pollack|first1=Andrew| name-list-style = vanc |access-date=21 April 2016}}</ref>

GMOs have been developed that modify the quality of produce by increasing the nutritional value or providing more industrially useful qualities or quantities.<ref name="Deborah B. Whitman 2000">{{cite web|title=Genetically Modified Foods: Harmful or Helpful?|year=2000|first=Deborah B.|last=Whitman|name-list-style=vanc|url=http://www.csa.com/discoveryguides/gmfood/overview.php|access-date=9 July 2010|archive-date=16 February 2015|archive-url=https://web.archive.org/web/20150216145707/http://www.csa.com/discoveryguides/gmfood/overview.php}}</ref> The [[Amflora]] potato produces a more industrially useful blend of starches. [[Genetically modified soybean|Soybeans]] and [[Genetically modified canola|canola]] have been genetically modified to produce more healthy oils.<ref>Rapeseed (canola) has been genetically engineered to modify its oil content with a gene encoding a "12:0 thioesterase" (TE) enzyme from the California bay plant ([[Umbellularia californica]]) to increase medium length fatty acids, see: [http://www.geo-pie.cornell.edu/traits/altoil.html Geo-pie.cornell.edu] {{webarchive|url=https://web.archive.org/web/20090705230132/http://www.geo-pie.cornell.edu/traits/altoil.html |date=5 July 2009 }}</ref><ref>{{cite journal | vauthors = Bomgardner MM | year = 2012 | title = Replacing Trans Fat: New crops from Dow Chemical and DuPont target food makers looking for stable, heart-healthy oils | url = http://cen.acs.org/articles/90/i11/Replacing-Trans-Fat.html | journal = Chemical and Engineering News | volume = 90 | issue = 11| pages = 30–32 | doi = 10.1021/cen-09011-bus1 }}</ref> The first commercialised GM food was a [[Flavr Savr|tomato]] that had delayed ripening, increasing its [[shelf life]].<ref>{{Cite journal|last1=Kramer|first1=Matthew G.|last2=Redenbaugh|first2=Keith| name-list-style = vanc |date=1994-01-01|title=Commercialization of a tomato with an antisense polygalacturonase gene: The FLAVR SAVR™ tomato story|journal=Euphytica|language=en|volume=79|issue=3|pages=293–97|doi=10.1007/BF00022530|bibcode=1994Euphy..79..293K |s2cid=45071333|issn=0014-2336}}</ref>

Plants and animals have been engineered to produce materials they do not normally make.  [[Pharming (genetics)|Pharming]] uses crops and animals as bioreactors to produce vaccines, drug intermediates, or the drugs themselves; the useful product is purified from the harvest and then used in the standard pharmaceutical production process.<ref>{{cite journal |doi=10.1051/agro:2007050 |title=Pharmaceutical crops in California, benefits and risks. A review |year=2008 |last1=Marvier |first1=Michelle | name-list-style = vanc |journal=Agronomy for Sustainable Development |volume=28 |issue=1 |pages=1–9|bibcode=2008AgSD...28....1M |s2cid=29538486 |url=https://hal.archives-ouvertes.fr/hal-00886450/file/hal-00886450.pdf |archive-url=https://web.archive.org/web/20180719040330/https://hal.archives-ouvertes.fr/hal-00886450/file/hal-00886450.pdf |archive-date=2018-07-19 |url-status=live }}</ref> Cows and goats have been engineered to express drugs and other proteins in their milk, and in 2009 the FDA approved a drug produced in goat milk.<ref>{{cite web|url=https://www.fda.gov/AnimalVeterinary/NewsEvents/FDAVeterinarianNewsletter/ucm190728.htm|archive-url=https://web.archive.org/web/20100111214152/http://www.fda.gov/AnimalVeterinary/NewsEvents/FDAVeterinarianNewsletter/ucm190728.htm|url-status=dead|archive-date=11 January 2010|title=FDA Approves First Human Biologic Produced by GE Animals|publisher=US Food and Drug Administration}}</ref><ref>{{cite web|title=GM cow milk 'could provide treatment for blood disease'|first=Paulo |last=Rebêlo| name-list-style = vanc |date=15 July 2004|publisher=SciDev|url=http://www.scidev.net/en/news/gm-cow-milk-could-provide-treatment-for-blood-dis.html}}</ref>

=== Other applications ===
Genetic engineering has potential applications in conservation and natural area management. Gene transfer through [[viral vector]]s has been proposed as a means of controlling invasive species as well as vaccinating threatened fauna from disease.<ref>{{cite journal | vauthors = Angulo E, Cooke B | title = First synthesize new viruses then regulate their release? The case of the wild rabbit | journal = Molecular Ecology | volume = 11 | issue = 12 | pages = 2703–9 | date = December 2002 | pmid = 12453252 | doi = 10.1046/j.1365-294X.2002.01635.x | bibcode = 2002MolEc..11.2703A | hdl = 10261/45541 | s2cid = 23916432 | hdl-access = free }}</ref> Transgenic trees have been suggested as a way to confer resistance to pathogens in wild populations.<ref>{{Cite journal| vauthors = Adams JM, Piovesan G, Strauss S, Brown S |date=2 August 2002|title=The Case for Genetic Engineering of Native and Landscape Trees against Introduced Pests and Diseases |journal=Conservation Biology |volume=16 |issue=4|pages=874–79|doi=10.1046/j.1523-1739.2002.00523.x  |bibcode=2002ConBi..16..874A |s2cid=86697592}}</ref> With the increasing risks of [[maladaptation]] in organisms as a result of [[climate change]] and other perturbations, facilitated adaptation through gene tweaking could be one solution to reducing extinction risks.<ref>{{cite journal | vauthors = Thomas MA, Roemer GW, Donlan CJ, Dickson BG, Matocq M, Malaney J | title = Ecology: Gene tweaking for conservation | journal = Nature | volume = 501 | issue = 7468 | pages = 485–6 | date = September 2013 | pmid = 24073449 | doi = 10.1038/501485a | doi-access = free }}</ref> Applications of genetic engineering in conservation are thus far mostly theoretical and have yet to be put into practice.

Genetic engineering is also being used to create [[microbial art]].<ref>{{cite web|title=Bio-artists bridge gap between arts, sciences: Use of living organisms is attracting attention and controversy|first=Jessica M. |last=Pasko| name-list-style = vanc |publisher=msnbc|url=http://www.nbcnews.com/id/17387568|archive-url=https://web.archive.org/web/20131004234217/http://www.nbcnews.com/id/17387568/|url-status=dead|archive-date=4 October 2013|date=2007-03-04}}</ref> Some bacteria have been genetically engineered to create black and white photographs.<ref>{{cite web|title=Genetically Modified Bacteria Produce Living Photographs|first=Joab |last=Jackson| name-list-style = vanc |publisher=National Geographic News|date=6 December 2005|url=http://news.nationalgeographic.com/news/2005/12/1206_051206_bacteria_photos.html|archive-url=https://web.archive.org/web/20051216101532/http://news.nationalgeographic.com/news/2005/12/1206_051206_bacteria_photos.html|url-status=dead|archive-date=16 December 2005}}</ref> Novelty items such as lavender-colored [[Dianthus caryophyllus#Colors|carnations]],<ref name="physorg">{{Cite web|title=Plant gene replacement results in the world's only blue rose|url=https://phys.org/news/2005-04-gene-results-world-blue-rose.html|access-date=2023-03-30|website=phys.org|language=en}}</ref> [[blue rose]]s,<ref>{{cite journal | vauthors = Katsumoto Y, Fukuchi-Mizutani M, Fukui Y, Brugliera F, Holton TA, Karan M, Nakamura N, Yonekura-Sakakibara K, Togami J, Pigeaire A, Tao GQ, Nehra NS, Lu CY, Dyson BK, Tsuda S, Ashikari T, Kusumi T, Mason JG, Tanaka Y | title = Engineering of the rose flavonoid biosynthetic pathway successfully generated blue-hued flowers accumulating delphinidin | journal = Plant & Cell Physiology | volume = 48 | issue = 11 | pages = 1589–600 | date = November 2007 | pmid = 17925311 | doi = 10.1093/pcp/pcm131 | citeseerx = 10.1.1.319.8365 }}</ref> and [[GloFish|glowing fish]],<ref>{{Cite web|title=WIPO - Search International and National Patent Collections|url=https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2000049150|access-date=2023-03-30|website=patentscope.wipo.int}}</ref><ref>{{cite journal | vauthors = Stewart CN | title = Go with the glow: fluorescent proteins to light transgenic organisms | journal = Trends in Biotechnology | volume = 24 | issue = 4 | pages = 155–62 | date = April 2006 | pmid = 16488034 | doi = 10.1016/j.tibtech.2006.02.002 | url = http://plantsciences.utk.edu/pdf/stewart-TIBTECH-FPs-2006.pdf | access-date = 25 October 2017 | archive-date = 3 July 2010 | archive-url = https://web.archive.org/web/20100703194009/http://plantsciences.utk.edu/pdf/stewart-TIBTECH-FPs-2006.pdf }}</ref> have also been produced through genetic engineering.