Editing Genetically modified organism (section)

== Animals ==
{{Main|Genetically modified animal}}
The vast majority of genetically modified animals are at the research stage with the number close to entering the market remaining small.<ref name=":14">{{cite journal | vauthors = Forabosco F, Löhmus M, Rydhmer L, Sundström LF | title = Genetically modified farm animals and fish in agriculture: A review. | journal = Livestock Science | date = May 2013 | volume = 153 | issue = 1–3 | pages = 1–9 | doi = 10.1016/j.livsci.2013.01.002 }}</ref> As of 2018 only three genetically modified animals have been approved, all in the USA. A goat and a chicken have been engineered to produce medicines and a salmon has increased its own growth.<ref>{{Cite web|url=https://www.the-scientist.com/notebook/the-superpowers-of-genetically-modified-pigs-64513|title=The Superpowers of Genetically Modified Pigs|website=[[The Scientist (magazine)|The Scientist]] |access-date=5 February 2019}}</ref> Despite the differences and difficulties in modifying them, the end aims are much the same as for plants. GM animals are created for research purposes, production of industrial or therapeutic products, agricultural uses, or improving their health. There is also a market for creating genetically modified pets.<ref name="rudenko">Rudinko, Larisa (20). Guidance for industry. USA: Center for veterinary medicine [https://www.fda.gov/downloads/AnimalVeterinary/GuidanceComplianceEnforcement/GuidanceforIndustry/ucm113903.pdf/ Link.]</ref>

=== Mammals ===
{{Main|Genetically modified mammals}}

[[File:ChimericMouseWithPups.jpg|thumb|Some [[chimera (genetics)|chimeras]], like the blotched mouse shown, are created through genetic modification techniques like [[gene targeting]].]]

The process of genetically engineering mammals is slow, tedious, and expensive. However, new technologies are making genetic modifications easier and more precise.<ref name="Murray2010">Murray, Joo (20). [http://www.brainwaving.com/2010/07/28/genetically-modified-animals Genetically modified animals] {{Webarchive|url=https://web.archive.org/web/20191013112127/http://www.brainwaving.com/2010/07/28/genetically-modified-animals/ |date=13 October 2019 }}. Canada: Brainwaving</ref> The first transgenic mammals were produced by injecting viral DNA into embryos and then implanting the embryos in females.<ref name="Simian virus 40 DNA sequences in DN" /> The embryo would develop and it would be hoped that some of the genetic material would be incorporated into the reproductive cells. Then researchers would have to wait until the animal reached breeding age and then offspring would be screened for the presence of the gene in every cell. The development of the [[CRISPR]]-Cas9 gene editing system as a cheap and fast way of directly modifying [[germ cell]]s, effectively halving the amount of time needed to develop genetically modified mammals.<ref>{{cite web|url=https://www.pbs.org/wgbh/nova/article/crispr-animals/|title=How CRISPR is Spreading Through the Animal Kingdom|website=www.pbs.org|date=23 May 2018 |access-date=20 December 2018}}</ref>

[[File:Porcine-Model-of-Hemophilia-A-pone.0049450.s002.ogv|left|thumb|A [[porcine]] model of [[Haemophilia A|hemophilia A]]]]

Mammals are the best models for human disease, making genetic engineered ones vital to the discovery and development of cures and treatments for many serious diseases. Knocking out genes responsible for [[human genetic disorder]]s allows researchers to study the mechanism of the disease and to test possible cures. [[Genetically modified mouse|Genetically modified mice]] have been the most common mammals used in [[biomedical research]], as they are cheap and easy to manipulate. Pigs are also a good target as they have a similar body size and anatomical features, [[physiology]], [[Pathophysiology|pathophysiological]] response and diet.<ref name=":13">{{cite journal | vauthors = Perleberg C, Kind A, Schnieke A | title = Genetically engineered pigs as models for human disease | journal = Disease Models & Mechanisms | volume = 11 | issue = 1 | date = January 2018 | pmid = 29419487 | pmc = 5818075 | doi = 10.1242/dmm.030783 }}</ref> Nonhuman primates are the most similar model organisms to humans, but there is less public acceptance towards using them as research animals.<ref>{{cite journal | vauthors = Sato K, Sasaki E | title = Genetic engineering in nonhuman primates for human disease modeling | journal = Journal of Human Genetics | volume = 63 | issue = 2 | pages = 125–131 | date = February 2018 | pmid = 29203824 | doi = 10.1038/s10038-017-0351-5 | pmc = 8075926 | doi-access = free }}</ref> In 2009, scientists announced that they had successfully transferred a gene into a [[primate]] species ([[marmoset]]s) for the first time.<ref>{{cite journal | vauthors = Sasaki E, Suemizu H, Shimada A, Hanazawa K, Oiwa R, Kamioka M, Tomioka I, Sotomaru Y, Hirakawa R, Eto T, Shiozawa S, Maeda T, Ito M, Ito R, Kito C, Yagihashi C, Kawai K, Miyoshi H, Tanioka Y, Tamaoki N, Habu S, Okano H, Nomura T | title = Generation of transgenic non-human primates with germline transmission | journal = Nature | volume = 459 | issue = 7246 | pages = 523–7 | date = May 2009 | pmid = 19478777 | doi = 10.1038/nature08090 | bibcode = 2009Natur.459..523S | s2cid = 4404433 }}</ref><ref>{{cite journal | vauthors = Schatten G, Mitalipov S | title = Developmental biology: Transgenic primate offspring | journal = Nature | volume = 459 | issue = 7246 | pages = 515–6 | date = May 2009 | pmid = 19478771 | pmc = 2777739 | doi = 10.1038/459515a | bibcode = 2009Natur.459..515S }}</ref> Their first research target for these marmosets was [[Parkinson's disease]], but they were also considering [[amyotrophic lateral sclerosis]] and [[Huntington's disease]].<ref>{{cite journal | vauthors = Cyranoski D | title = Marmoset model takes centre stage | journal = Nature | volume = 459 | issue = 7246 | pages = 492 | date = May 2009 | pmid = 19478751 | doi = 10.1038/459492a | doi-access = free }}</ref>

Human proteins expressed in mammals are more likely to be similar to their natural counterparts than those expressed in plants or microorganisms. Stable expression has been accomplished in sheep, pigs, rats and other animals.  In 2009, the first human biological drug produced from such an animal, a [[goat]], was approved. The drug, [[ATryn]], is an [[anticoagulant]] which reduces the probability of [[blood clot]]s during [[surgery]] or [[childbirth]] and is extracted from the goat's milk.<ref>Britt Erickson, 10 February 2009, for ''Chemical & Engineering News''. [https://archive.today/20130112055323/http://pubs.acs.org/cen/news/87/i07/8707notw5.html FDA Approves Drug From Transgenic Goat Milk] Accessed 6 October 2012</ref> Human [[Alpha-1 antitrypsin|alpha-1-antitrypsin]] is another protein that has been produced from goats and is used in treating humans with this deficiency.<ref>{{cite journal | vauthors = Spencer LT, Humphries JE, Brantly ML | title = Antibody response to aerosolized transgenic human alpha1-antitrypsin | journal = The New England Journal of Medicine | volume = 352 | issue = 19 | pages = 2030–1 | date = May 2005 | pmid = 15888711 | doi = 10.1056/nejm200505123521923 | doi-access = free }}</ref> Another medicinal area is in creating pigs with greater capacity for [[Organ transplantation|human organ transplants]] ([[xenotransplantation]]). Pigs have been genetically modified so that their organs can no longer carry retroviruses<ref>{{Cite web|url=https://www.nytimes.com/2015/10/20/science/editing-of-pig-dna-may-lead-to-more-organs-for-people.html |archive-url=https://ghostarchive.org/archive/20220102/https://www.nytimes.com/2015/10/20/science/editing-of-pig-dna-may-lead-to-more-organs-for-people.html |archive-date=2 January 2022 |url-access=limited |url-status=live|title=Editing of Pig DNA May Lead to More Organs for People l| vauthors = Zimmer C |date=15 October 2015|work=The New York Times}}{{cbignore}}</ref> or have modifications to reduce the chance of rejection.<ref>{{cite journal | vauthors = Zeyland J, Gawrońska B, Juzwa W, Jura J, Nowak A, Słomski R, Smorąg Z, Szalata M, Woźniak A, Lipiński D | title = Transgenic pigs designed to express human α-galactosidase to avoid humoral xenograft rejection | journal = Journal of Applied Genetics | volume = 54 | issue = 3 | pages = 293–303 | date = August 2013 | pmid = 23780397 | pmc = 3720986 | doi = 10.1007/s13353-013-0156-y }}</ref><ref>{{Cite web|url=https://www.iflscience.com/health-and-medicine/pig-heart-transplants-humans-could-be-their-way/|title=Pig Heart Transplants For Humans Could Be on Their Way|website=IFLScience|date=30 April 2014 }}</ref> Chimeric pigs could carry fully human organs.<ref name=":13" /><ref>{{cite journal | vauthors = Wu J, Platero-Luengo A, Sakurai M, Sugawara A, Gil MA, Yamauchi T, Suzuki K, Bogliotti YS, Cuello C, Morales Valencia M, Okumura D, Luo J, Vilariño M, Parrilla I, Soto DA, Martinez CA, Hishida T, Sánchez-Bautista S, Martinez-Martinez ML, Wang H, Nohalez A, Aizawa E, Martinez-Redondo P, Ocampo A, Reddy P, Roca J, Maga EA, Esteban CR, Berggren WT, Nuñez Delicado E, Lajara J, Guillen I, Guillen P, Campistol JM, Martinez EA, Ross PJ, Izpisua Belmonte JC | title = Interspecies Chimerism with Mammalian Pluripotent Stem Cells | journal = Cell | volume = 168 | issue = 3 | pages = 473–486.e15 | date = January 2017 | pmid = 28129541 | pmc = 5679265 | doi = 10.1016/j.cell.2016.12.036 }}</ref> The first human transplant of a genetically modified pig heart occurred in 2023,<ref>{{Cite web |agency=Associated Press |date=2023-11-01 |title=Man who received the second pig heart transplant dies, hospital says |url=https://www.nbcnews.com/news/us-news/man-received-second-pig-heart-transplant-dies-hospital-says-rcna123104 |access-date=2023-11-01 |website=www.nbcnews.com |language=en}}</ref> and kidney in 2024.<ref name="3/21/24nyt">{{cite news |last1=Rabin |first1=Roni Caryn |title=Surgeons Transplant Pig Kidney Into a Patient, a Medical Milestone |url=https://www.nytimes.com/2024/03/21/health/pig-kidney-organ-transplant.html |access-date=22 March 2024 |work=New York Times |date=21 March 2024}}</ref><ref name="3/21/24CNN">{{cite news |last1=Goodman |first1=Brenda |title=Pig kidney transplanted into living person for first time |url=https://www.cnn.com/2024/03/21/health/pig-kidney-transplant-living-person/index.html |access-date=22 March 2024 |work=CNN |date=21 March 2024 |language=en}}</ref>

Livestock are modified with the intention of improving economically important traits such as growth-rate, quality of meat, milk composition, disease resistance and survival. Animals have been engineered to grow faster, be healthier<ref>{{cite journal | vauthors = Lai L, Kang JX, Li R, Wang J, Witt WT, Yong HY, Hao Y, Wax DM, Murphy CN, Rieke A, Samuel M, Linville ML, Korte SW, Evans RW, Starzl TE, Prather RS, Dai Y | title = Generation of cloned transgenic pigs rich in omega-3 fatty acids | journal = Nature Biotechnology | volume = 24 | issue = 4 | pages = 435–6 | date = April 2006 | pmid = 16565727 | pmc = 2976610 | doi = 10.1038/nbt1198 }}</ref> and resist diseases.<ref>{{cite news |url= https://www.theguardian.com/environment/2018/jun/24/genetically-engineered-animals-the-five-controversial-science |title=Genetically modified animals| vauthors = Tucker I |date=24 June 2018|work=The Guardian |access-date=21 December 2018 |issn=0261-3077}}</ref> Modifications have also improved the wool production of sheep and udder health of cows.<ref name=":14" /> Goats have been genetically engineered to produce milk with strong spiderweb-like silk proteins in their milk.<ref>{{cite web | vauthors = Zyga L | date = 2010 | url = http://phys.org/news194539934.html/ | title = Scientist bred goats that produce spider silk | work = Phys.org | archive-url =  https://web.archive.org/web/20150430100830/http://phys.org/news194539934.html/ | url-status = dead | archive-date = 30 April 2015 }}</ref> A GM pig called [[Enviropig]] was created with the capability of digesting plant [[phosphorus]] more efficiently than conventional pigs.<ref name="Guelph">{{cite web | publisher = University of Guelph | location = Canada  | date = 2010 | url = http://www.uoguelph.ca/enviropig/index.shtml | title = Enviropig | archive-url =  https://web.archive.org/web/20160130104858/http://www.uoguelph.ca/enviropig/index.shtml | archive-date = 30 January 2016}}</ref><ref>{{cite web | vauthors = Schimdt S | url  = http://www.canada.com/technology/science/Genetically+engineered+pigs+killed+after+funding+ends/6819844/story.html | title = Genetically engineered pigs killed after funding ends | work = Postmedia News | date = 22 June 2012 | access-date = 31 July 2012 }}</ref> They could reduce water pollution since they excrete 30 to 70% less phosphorus in manure.<ref name="Guelph" /><ref name="Canada">{{cite web |url= http://www.uoguelph.ca/enviropig/environmental_benefits.shtml |title=Enviropig – Environmental Benefits| publisher = University of Guelph| location = Canada |archive-url = https://web.archive.org/web/20100227041057/http://www.uoguelph.ca/enviropig/environmental_benefits.shtml |archive-date = 27 February 2010 |url-status=dead |access-date=8 March 2010 }}</ref> [[Dairy cows]] have been genetically engineered to produce milk that would be the same as human breast milk.<ref name="richardgray">{{cite web | vauthors = Gray R | date = 2011 | url = https://www.telegraph.co.uk/earth/agriculture/geneticmodification/8423536/Genetically-modified-cows-produce-human-milk.html | archive-url = https://web.archive.org/web/20110404101149/http://www.telegraph.co.uk/earth/agriculture/geneticmodification/8423536/Genetically-modified-cows-produce-human-milk.html | url-status = dead | archive-date = 4 April 2011 | title = Genetically modified cows produce 'human' milk }}</ref> This could potentially benefit mothers who cannot produce breast milk but want their children to have breast milk rather than formula.<ref>{{cite web |url= http://www.classicalmedicinejournal.com/the-classical-medicine-journal/2011/4/13/genetically-modified-cows-producing-human-milk.html|title=Genetically modified cows producing human milk| work = Classical Medicine Journal|date=14 April 2010|archive-url=https://web.archive.org/web/20141106050820/http://www.classicalmedicinejournal.com/the-classical-medicine-journal/2011/4/13/genetically-modified-cows-producing-human-milk.html|archive-date=6 November 2014|url-status=dead}}</ref><ref>{{cite news|url=https://www.telegraph.co.uk/news/worldnews/southamerica/argentina/8569687/Scientists-create-cow-that-produces-human-milk.html|title=Scientists create cow that produces 'human' milk| vauthors = Yapp R |date=11 June 2011|work=[[The Daily Telegraph]]|access-date=15 June 2012|location=London }}</ref> Researchers have also developed a genetically engineered cow that produces allergy-free milk.<ref>{{cite journal | vauthors = Jabed A, Wagner S, McCracken J, Wells DN, Laible G | title = Targeted microRNA expression in dairy cattle directs production of β-lactoglobulin-free, high-casein milk | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 109 | issue = 42 | pages = 16811–6 | date = October 2012 | pmid = 23027958 | pmc = 3479461 | doi = 10.1073/pnas.1210057109 | bibcode = 2012PNAS..10916811J | doi-access = free }}</ref>

[[File:GFP Mice 01.jpg|thumb|Mice expressing the [[green fluorescent protein]]]]

Scientists have genetically engineered several organisms, including some mammals, to include [[green fluorescent protein]] (GFP), for research purposes.<ref>{{cite web | title=Green fluorescent protein takes Nobel prize | url=http://www.rsc.org/chemistryworld/News/2008/October/08100802.asp | publisher=Lewis Brindley | access-date=31 May 2015}}</ref> GFP and other similar reporting genes allow easy visualization and localization of the products of the genetic modification.<ref name=":32">{{cite book | vauthors = Alberts B, Johnson A, Lewis J, Raff M, Roberts K, Walter P |date=2002 |chapter=Studying Gene Expression and Function | title = Molecular Biology of the Cell |publisher=Garland Science | edition = 4th | chapter-url= https://www.ncbi.nlm.nih.gov/books/NBK26818/ }}</ref> Fluorescent pigs have been bred to study human organ transplants, regenerating ocular [[photoreceptor cell]]s, and other topics.<ref name="Randall">{{cite journal | vauthors = Randall S | editor-first1 = Stephen | editor-first2 = Michael | editor-last1 = e. Harding | editor-last2 = p. Tombs | title = Genetically Modified Pigs for Medicine and Agriculture | journal = Biotechnology and Genetic Engineering Reviews | volume = 25 | pages = 245–66 | date = 2008  | doi = 10.7313/upo9781904761679.011 | doi-broken-date = 1 November 2024 | pmid = 21412358 | isbn = 978-1-904761-67-9 | url = http://www.nottingham.ac.uk/ncmh/BGER/pdf/volume_25/11-Prather.pdf | archive-url= https://web.archive.org/web/20140326024622/http://www.nottingham.ac.uk/ncmh/BGER/pdf/volume_25/11-Prather.pdf | url-status = dead| archive-date = 26 March 2014 }}</ref> In 2011, green-fluorescent cats were created to help find therapies for [[HIV/AIDS]] and other diseases<ref name="Wongsrikeao_2011">{{cite journal | vauthors = Wongsrikeao P, Saenz D, Rinkoski T, Otoi T, Poeschla E | title = Antiviral restriction factor transgenesis in the domestic cat | journal = Nature Methods | volume = 8 | issue = 10 | pages = 853–9 | date = September 2011 | pmid = 21909101 | pmc = 4006694 | doi = 10.1038/nmeth.1703 | author-link5 = Eric Poeschla }}</ref> as [[feline immunodeficiency virus]] is related to [[HIV]].<ref>{{cite web | author = Staff | date = 3 April 2012 | url = https://www.niaid.nih.gov/topics/hivaids/understanding/biology/Pages/biology.aspx | title = Biology of HIV | archive-url = https://web.archive.org/web/20140411035138/https://www.niaid.nih.gov/topics/hivaids/understanding/biology/Pages/biology.aspx | archive-date=11 April 2014 | publisher = National Institute of Allergy and Infectious Diseases | url-status = dead }}</ref>

There have been suggestions that genetic engineering could be used to bring animals [[De-extinction|back from extinction]]. It involves changing the genome of a close living relative to resemble the extinct one and is currently being attempted with the [[passenger pigeon]].<ref>{{Cite web|url=https://www.scientificamerican.com/article/ancient-dna-could-return-passenger-pigeons-to-the-sky/|title=Ancient DNA Could Return Passenger Pigeons to the Sky| vauthors = Biello D |website=Scientific American|access-date=23 December 2018}}</ref> Genes associated with the [[woolly mammoth]] have been added to the genome of an [[African elephant|African Elephant]], although the lead researcher says he has no intention of creating live elephants and transferring all the genes and reversing years of genetic evolution is a long way from being feasible.<ref>{{Cite web|url=https://www.newscientist.com/article/2121503-can-we-grow-woolly-mammoths-in-the-lab-george-church-hopes-so/|title=Can we grow woolly mammoths in the lab? George Church hopes so | vauthors = Sarchet P |website=New Scientist|access-date=23 December 2018}}</ref><ref>{{Cite web|url=https://medium.com/@johnhawks/how-mammoth-cloning-became-fake-news-1e3a80e54d42|title=How mammoth cloning became fake news| vauthors = Hawks J |date=19 February 2017|website=John Hawks|access-date=20 January 2019}}</ref> It is more likely that scientists could use this technology to conserve endangered animals by bringing back lost diversity or transferring evolved genetic advantages from adapted organisms to those that are struggling.<ref>{{cite journal | vauthors = Shapiro B | title = Mammoth 2.0: will genome engineering resurrect extinct species? | journal = Genome Biology | volume = 16 | issue = 1 | pages = 228 | date = November 2015 | pmid = 26530525 | pmc = 4632474 | doi = 10.1186/s13059-015-0800-4 | doi-access = free }}</ref>

==== Humans ====
[[Gene therapy]]<ref>{{cite journal | vauthors = Selkirk SM | title = Gene therapy in clinical medicine | journal = Postgraduate Medical Journal | volume = 80 | issue = 948 | pages = 560–70 | date = October 2004 | pmid = 15466989 | pmc = 1743106 | doi = 10.1136/pgmj.2003.017764 }}</ref> uses genetically modified viruses to deliver genes which can cure disease in humans. Although gene therapy is still relatively new, it has had some successes. It has been used to treat [[genetic disorder]]s such as [[severe combined immunodeficiency]],<ref>{{cite journal | vauthors = Cavazzana-Calvo M, Fischer A | title = Gene therapy for severe combined immunodeficiency: are we there yet? | journal = The Journal of Clinical Investigation | volume = 117 | issue = 6 | pages = 1456–65 | date = June 2007 | pmid = 17549248 | pmc = 1878528 | doi = 10.1172/JCI30953 }}</ref> and [[Adeno associated virus and gene therapy of the human retina|Leber's congenital amaurosis]].<ref>{{cite web | vauthors = Richards S | date = 6 November 2012 | url = http://www.the-scientist.com/?articles.view/articleNo/33166/title/Gene-Therapy-Arrives-in-Europe/ | title = Gene therapy arrives in Europe | work = The Scientist }}</ref> Treatments are also being developed for a range of other currently incurable diseases, such as [[cystic fibrosis]],<ref>{{cite journal | vauthors = Rosenecker J, Huth S, Rudolph C | title = Gene therapy for cystic fibrosis lung disease: current status and future perspectives | journal = Current Opinion in Molecular Therapeutics | volume = 8 | issue = 5 | pages = 439–45 | date = October 2006 | pmid = 17078386 }}</ref> [[sickle cell anemia]],<ref>{{cite journal | vauthors = Persons DA, Nienhuis AW | title = Gene therapy for the hemoglobin disorders | journal = Current Hematology Reports | volume = 2 | issue = 4 | pages = 348–55 | date = July 2003 | pmid = 12901333 }}</ref> [[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, randomized 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><ref>Gallaher, James (17 March 2011). [https://www.bbc.co.uk/news/health-12758230 "Gene therapy 'treats' Parkinson's disease"]. BBC News Health. Retrieved 24 April 2011</ref> [[cancer]],<ref>{{cite web | vauthors = Urbina Z | date = 12 February 2013 | url = http://www.united-academics.org/magazine/health-medicine/killing-liver-cancer-with-a-genetically-engineered-virus/ | title = Genetically Engineered Virus Fights Liver Cancer | archive-url = https://web.archive.org/web/20130216041212/http://www.united-academics.org/magazine/health-medicine/killing-liver-cancer-with-a-genetically-engineered-virus/ | url-status = dead | archive-date=16 February 2013 | publisher = United Academics | access-date = 15 February 2013 }}</ref><ref>{{cite news | title = Treatment for Leukemia Is Showing Early Promise | url = https://www.nytimes.com/2011/08/11/health/research/11cancer.html | work = The New York Times | agency = [[Associated Press]] | page = A15 | date = 11 August 2011 | access-date = 21 January 2013}}</ref><ref>{{cite web | vauthors = Coghlan A | date = 26 March 2013 | url = https://www.newscientist.com/article/mg21729104.100-gene-therapy-cures-leukaemia-in-eight-days.html | title = Gene therapy cures leukaemia in eight days | work = New Scientist | access-date = 15 April 2013 }}</ref> [[diabetes]],<ref>{{cite web|url=https://www.newscientist.com/article/mg21729044.800-gene-therapy-cures-diabetic-dogs.html|title=Gene therapy cures diabetic dogs|date=13 February 2013|work=New Scientist|access-date=15 February 2013}}</ref> [[heart disease]]<ref>{{cite web | date = 30 April 2013 | url = http://www.bhf.org.uk/default.aspx?page=16039 | title = New gene therapy trial gives hope to people with heart failure | work = British Heart Foundation | access-date = 5 May 2013 }}</ref> and [[muscular dystrophy]].<ref>{{cite journal | vauthors = Foster K, Foster H, Dickson JG | title = Gene therapy progress and prospects: Duchenne muscular dystrophy | journal = Gene Therapy | volume = 13 | issue = 24 | pages = 1677–85 | date = December 2006 | pmid = 17066097 | doi = 10.1038/sj.gt.3302877 | doi-access = free }}</ref> These treatments only effect [[somatic cell]]s, meaning any changes would not be inheritable. [[Germline]] gene therapy results 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|archive-url=https://web.archive.org/web/20010805085535/http://www.cioms.ch/frame_1990_texts_of_guidelines.htm|archive-date=5 August 2001|url-status=dead}}</ref><ref name="Smith_2010">{{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|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=2 January 2022 |url-access=limited |url-status=live|title=Chinese Scientists Edit Genes of Human Embryos, Raising Concerns | vauthors = Kolata G |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 | 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 | doi = 10.1007/s13238-015-0153-5 | pmc = 4417674 }}</ref> In November 2018, [[He Jiankui]] announced that he had [[Genome editing|edited the genomes]] of two human embryos, in an attempt to disable the ''[[CCR5]]'' gene, which codes for a receptor that HIV uses to enter cells. He said that twin girls, [[Lulu and Nana]], had been born a few weeks earlier and that they carried functional copies of CCR5 along with disabled CCR5 ([[mosaicism]]) and were still vulnerable to HIV.  The work was widely condemned as unethical, dangerous, and premature.<ref>{{cite news|url=https://www.statnews.com/2018/11/28/chinese-scientist-defends-creating-gene-edited-babies/|title=Amid uproar, Chinese scientist defends creating gene-edited babies – STAT| vauthors = Begley S |date=28 November 2018|work=STAT}}</ref>

=== Fish ===
{{Main|Genetically modified fish}}

{{multiple image
 | align     = right
 | footer    = When exposed to 13&nbsp;°C water the zebrafish modified to express a [[carp]] [[creatine kinase]] ('''right''') maintained swimming behavior, while wild type zebrafish ('''left''') could not.<ref>{{cite journal | vauthors = Wang Q, Tan X, Jiao S, You F, Zhang PJ | title = Analyzing cold tolerance mechanism in transgenic zebrafish (Danio rerio) | journal = PLOS ONE | volume = 9 | issue = 7 | pages = e102492 | date = 24 July 2014 | pmid = 25058652 | pmc = 4109919 | doi = 10.1371/journal.pone.0102492 | bibcode = 2014PLoSO...9j2492W | doi-access = free }}</ref> | image1    = Analyzing-Cold-Tolerance-Mechanism-in-Transgenic-Zebrafish-(Danio-rerio)-pone.0102492.s009.ogv | width1    = 180
 | image2    = Analyzing-Cold-Tolerance-Mechanism-in-Transgenic-Zebrafish-(Danio-rerio)-pone.0102492.s010.ogv | width2    = 180
}}
Genetically modified fish are used for scientific research, as pets and as a food source. [[Aquaculture]] is a growing industry, currently providing over half the consumed fish worldwide.<ref>{{cite web|url=https://www.sciencedaily.com/releases/2009/09/090907162320.htm|title=Half of Fish Consumed Globally Is Now Raised on Farms, Study Finds|website=ScienceDaily|access-date=21 December 2018}}</ref> Through genetic engineering it is possible to increase growth rates, reduce food intake, remove allergenic properties, increase cold tolerance and provide disease resistance. Fish can also be used to detect aquatic pollution or function as bioreactors.<ref>{{cite journal | vauthors = Tonelli FM, Lacerda SM, Tonelli FC, Costa GM, de França LR, Resende RR | title = Progress and biotechnological prospects in fish transgenesis | journal = Biotechnology Advances | volume = 35 | issue = 6 | pages = 832–844 | date = November 2017 | pmid = 28602961 | doi = 10.1016/j.biotechadv.2017.06.002 }}</ref>

Several groups have been developing [[zebrafish]] to detect pollution by attaching fluorescent proteins to genes activated by the presence of pollutants. The fish will then glow and can be used as environmental sensors.<ref>{{cite journal|vauthors=Nebert DW, Stuart GW, Solis WA, Carvan MJ|date=January 2002|title=Use of reporter genes and vertebrate DNA motifs in transgenic zebrafish as sentinels for assessing aquatic pollution|journal=Environmental Health Perspectives|volume=110|issue=1|pages=A15|doi=10.1289/ehp.110-1240712|pmc=1240712|pmid=11813700}}</ref><ref>{{cite journal|vauthors=Mattingly CJ, McLachlan JA, Toscano WA|date=August 2001|title=Green fluorescent protein (GFP) as a marker of aryl hydrocarbon receptor (AhR) function in developing zebrafish (Danio rerio)|journal=Environmental Health Perspectives|volume=109|issue=8|pages=845–849|doi=10.1289/ehp.01109845|pmc=1240414|pmid=11564622|bibcode=2001EnvHP.109..845M }}</ref> The [[GloFish]] is a brand of genetically modified fluorescent [[zebrafish]] with bright red, green, and orange fluorescent color. It was originally developed by one of the groups to detect pollution, but is now part of the ornamental fish trade, becoming the first genetically modified animal to become publicly available as a pet when in 2003 it was introduced for sale in the USA.<ref>{{cite journal|vauthors=Hallerman E|date=June 2004|title=Glofish, the first GM animal commercialized: profits amid controversy.|url=http://www.isb.vt.edu/articles/jun0405.htm|journal=ISB News Report}}</ref>

GM fish are widely used in basic research in genetics and development. Two species of fish, zebrafish and [[Oryzias latipes|medaka]], are most commonly modified because they have optically clear [[Chorion (egg)|chorions]] (membranes in the egg), rapidly develop, and the one-cell embryo is easy to see and microinject with transgenic DNA.<ref>{{cite book | vauthors = Hackett PB, Ekker SE, Essner JJ | date = 2004 | chapter = Chapter 16: Applications of transposable elements in fish for transgenesis and functional genomics | title = Fish Development and Genetics | veditors = Gong Z, Korzh V | publisher = World Scientific, Inc. | pages = 532–80 }}</ref> Zebrafish are model organisms for developmental processes, [[Regeneration (biology)|regeneration]], genetics, behavior, disease mechanisms and toxicity testing.<ref>{{cite journal| vauthors = Meyers JR |date=2018|title=Zebrafish: Development of a Vertebrate Model Organism |journal=Current Protocols in Essential Laboratory Techniques |volume=16 |issue=1 |page=e19|doi=10.1002/cpet.19 |doi-access=free }}</ref> Their transparency allows researchers to observe developmental stages, intestinal functions and tumour growth.<ref>{{cite journal | vauthors = Lu JW, Ho YJ, Ciou SC, Gong Z | title = Innovative Disease Model: Zebrafish as an In Vivo Platform for Intestinal Disorder and Tumors | journal = Biomedicines | volume = 5 | issue = 4 | page = 58 | date = September 2017 | pmid = 28961226 | pmc = 5744082 | doi = 10.3390/biomedicines5040058 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Barriuso J, Nagaraju R, Hurlstone A | title = Zebrafish: a new companion for translational research in oncology | journal = Clinical Cancer Research | volume = 21 | issue = 5 | pages = 969–75 | date = March 2015 | pmid = 25573382 | pmc = 5034890 | doi = 10.1158/1078-0432.CCR-14-2921 }}</ref> The generation of transgenic protocols (whole organism, cell or tissue specific, tagged with reporter genes) has increased the level of information gained by studying these fish.<ref>{{cite journal | vauthors = Burket CT, Montgomery JE, Thummel R, Kassen SC, LaFave MC, Langenau DM, Zon LI, Hyde DR | display-authors = 6 | title = Generation and characterization of transgenic zebrafish lines using different ubiquitous promoters | journal = Transgenic Research | volume = 17 | issue = 2 | pages = 265–79 | date = April 2008 | pmid = 17968670 | pmc = 3660017 | doi = 10.1007/s11248-007-9152-5 }}</ref>

GM fish have been developed with promoters driving an over-production of [[growth hormone]] for use in the [[aquaculture]] industry to increase the speed of development and potentially reduce fishing pressure on wild stocks. This has resulted in dramatic growth enhancement in several species, including [[salmon]],<ref name="nature salmon">{{cite journal | vauthors = Du SJ, Gong Z, Fletcher GL, Shears MA, King MJ, Idler DR, Hew CL | year = 1992 | title = Growth Enhancement in Transgenic Atlantic Salmon by the Use of an 'All Fish' Chimeric Growth Hormone Gene Construct | journal = Nature Biotechnology | volume = 10 | issue = 2| pages = 176–181 | doi=10.1038/nbt0292-176 | pmid = 1368229| s2cid = 27048646 }}</ref> [[trout]]<ref name="nature trout">{{cite journal | vauthors = Devlin RH, Biagi CA, Yesaki TY, Smailus DE, Byatt JC | title = Growth of domesticated transgenic fish | journal = Nature | volume = 409 | issue = 6822 | pages = 781–782 | date = February 2001 | pmid = 11236982 | doi = 10.1038/35057314 | bibcode = 2001Natur.409..781D | s2cid = 5293883 }}</ref> and [[tilapia]].<ref name="tilapia">{{cite journal | vauthors = Rahman MA | display-authors = et al | year = 2001 | title = Growth and nutritional trials on transgenic Nile tilapia containing an exogenous fish growth hormone gene | journal = Journal of Fish Biology | volume = 59 | issue = 1| pages = 62–78 | doi=10.1111/j.1095-8649.2001.tb02338.x| bibcode = 2001JFBio..59...62R }}</ref> [[AquaBounty Technologies]], a biotechnology company, have produced a salmon (called [[AquAdvantage salmon]]) that can mature in half the time as wild salmon.<ref name="NYT2012">{{cite news| vauthors = Pollack A |title=Engineered Fish Moves a Step Closer to Approval|url=https://www.nytimes.com/2012/12/22/business/gene-altered-fish-moves-closer-to-federal-approval.html |archive-url=https://ghostarchive.org/archive/20220102/https://www.nytimes.com/2012/12/22/business/gene-altered-fish-moves-closer-to-federal-approval.html |archive-date=2 January 2022 |url-access=limited |url-status=live|newspaper=The New York Times|date=21 December 2012}}{{cbignore}}</ref> It obtained regulatory approval in 2015, the first non-plant GMO food to be commercialized.<ref>{{cite web|url=https://www.fda.gov/ForConsumers/ConsumerUpdates/ucm472487.htm|title=FDA Has Determined That the AquAdvantage Salmon is as Safe to Eat as Non-GE Salmon|website=U.S. Food & Drug Administration|date=19 November 2015|access-date=9 February 2018}}</ref> As of August 2017, GMO salmon is being sold in Canada.<ref>{{Cite news|url=https://www.scientificamerican.com/article/first-genetically-engineered-salmon-sold-in-canada/|title=First Genetically Engineered Salmon Sold in Canada| vauthors = Waltz E |work=Scientific American|access-date=8 August 2017}}</ref> Sales in the US started in May 2021.<ref>{{cite web |url=https://apnews.com/article/whole-foods-market-inc-lifestyle-health-coronavirus-pandemic-technology-a4ef4f24801f62ac65918e4560d7eb8a|title=Genetically modified salmon head to US dinner plates |last=Smith |first=Casey |date=21 May 2021 |website=AP News |access-date=6 August 2021}}</ref>

=== Insects ===
{{See also|Genetically modified insect}}
[[File:Genetic-Modifiers-of-MeCP2-Function-in-Drosophila-pgen.1000179.s006.ogv|thumb|[[Overexpression]] of [[MECP2|methyl-CpG–binding protein 2]] in ''[[Drosophila]]'' impairs climbing ability ('''right''') compared to the control group ('''left''').<ref>{{cite journal | vauthors = Cukier HN, Perez AM, Collins AL, Zhou Z, Zoghbi HY, Botas J | title = Genetic modifiers of MeCP2 function in Drosophila | journal = PLOS Genetics | volume = 4 | issue = 9 | pages = e1000179 | date = September 2008 | pmid = 18773074 | pmc = 2518867 | doi = 10.1371/journal.pgen.1000179 | doi-access = free }}</ref>]]
In biological research, transgenic fruit flies (''[[Drosophila melanogaster]]'') are [[model organism]]s used to study the effects of genetic changes on development.<ref>{{cite web|url=http://www.genome.gov/25520307|title=Online Education Kit: 1981–82: First Transgenic Mice and Fruit Flies|website=genome.gov}}</ref> Fruit flies are often preferred over other animals due to their short life cycle and low maintenance requirements. They also have a relatively simple genome compared to many [[vertebrates]], with typically only one copy of each gene, making [[Phenotype|phenotypic]] analysis easy.<ref>{{cite book | vauthors = Weasner BM, Zhu J, Kumar JP | chapter = FLPing Genes on and off in Drosophila | title = Site-Specific Recombinases | series = Methods in Molecular Biology | volume = 1642 | pages = 195–209 | date = 2017 | pmid = 28815502 | pmc = 5858584 | doi = 10.1007/978-1-4939-7169-5_13 | isbn = 978-1-4939-7167-1 }}</ref> ''Drosophila'' have been used to study genetics and inheritance, embryonic development, learning, behavior, and aging.<ref>{{cite journal |date=1 May 2011 |title=Drosophila – a versatile model in biology & medicine |journal=Materials Today |volume=14 |issue=5 |pages=190–195|doi=10.1016/S1369-7021(11)70113-4  | vauthors = Jennings BH |doi-access=free }}</ref> The discovery of [[Transposable element|transposons]], in particular the [[P element|p-element]], in ''Drosophila'' provided an early method to add transgenes to their genome, although this has been taken over by more modern gene-editing techniques.<ref>{{cite journal | vauthors = Ren X, Holsteens K, Li H, Sun J, Zhang Y, Liu LP, Liu Q, Ni JQ | title = Genome editing in Drosophila melanogaster: from basic genome engineering to the multipurpose CRISPR-Cas9 system | journal = Science China Life Sciences | volume = 60 | issue = 5 | pages = 476–489 | date = May 2017 | pmid = 28527116 | doi = 10.1007/s11427-017-9029-9 | s2cid = 255159948 }}</ref>

Due to their significance to human health, scientists are looking at ways to control mosquitoes through genetic engineering. Malaria-resistant mosquitoes have been developed in the laboratory by inserting a gene that reduces the development of the malaria parasite<ref>{{cite journal | vauthors = Corby-Harris V, Drexler A, Watkins de Jong L, Antonova Y, Pakpour N, Ziegler R, Ramberg F, Lewis EE, Brown JM, Luckhart S, Riehle MA | title = Activation of Akt signaling reduces the prevalence and intensity of malaria parasite infection and lifespan in Anopheles stephensi mosquitoes | journal = PLOS Pathogens | volume = 6 | issue = 7 | page = e1001003 | date = July 2010 | pmid = 20664791 | pmc = 2904800 | doi = 10.1371/journal.ppat.1001003 | veditors = Vernick KD | doi-access = free }}</ref> and then use [[homing endonuclease]]s to rapidly spread that gene throughout the male population (known as a [[gene drive]]).<ref>{{cite web | vauthors = Gallagher J | url = https://www.bbc.co.uk/news/health-13128327 | title = GM mosquitoes offer malaria hope | work = BBC News, Health | date = 20 April 2011 | access-date = 22 April 2011 }}</ref><ref>{{cite journal | vauthors = Windbichler N, Menichelli M, Papathanos PA, Thyme SB, Li H, Ulge UY, Hovde BT, Baker D, Monnat RJ, Burt A, Crisanti A | title = A synthetic homing endonuclease-based gene drive system in the human malaria mosquito | journal = Nature | volume = 473 | issue = 7346 | pages = 212–5 | date = May 2011 | pmid = 21508956 | pmc = 3093433 | doi = 10.1038/nature09937 | bibcode = 2011Natur.473..212W }}</ref> This approach has been taken further by using the gene drive to spread a lethal gene.<ref>{{cite journal | vauthors = Wise de Valdez MR, Nimmo D, Betz J, Gong HF, James AA, Alphey L, Black WC | title = Genetic elimination of dengue vector mosquitoes | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 108 | issue = 12 | pages = 4772–5 | date = March 2011 | pmid = 21383140 | pmc = 3064365 | doi = 10.1073/pnas.1019295108 | bibcode = 2011PNAS..108.4772W | doi-access = free }}</ref><ref name="Knapton">{{cite news| vauthors = Knapton S |title=Releasing millions of GM mosquitoes 'could solve zika crisis'|url=https://www.telegraph.co.uk/news/worldnews/zika/12143563/Releasing-millions-of-GM-mosquitoes-could-solve-zika-crisis.html|access-date=14 March 2016|newspaper=The Telegraph|date=6 February 2016}}</ref> In trials the populations of ''[[Aedes aegypti]]'' mosquitoes, the single most important carrier of dengue fever and Zika virus, were reduced by between 80% and by 90%.<ref>{{cite journal | vauthors = Harris AF, Nimmo D, McKemey AR, Kelly N, Scaife S, Donnelly CA, Beech C, Petrie WD, Alphey L | title = Field performance of engineered male mosquitoes | journal = Nature Biotechnology | volume = 29 | issue = 11 | pages = 1034–7 | date = October 2011 | pmid = 22037376 | doi = 10.1038/nbt.2019 | s2cid = 30862975 }}</ref><ref>Staff (March 2011) [https://web.archive.org/web/20111110150441/http://www.oxitec.com/wp-content/uploads/2011/03/OXITEC-Newsletter-March-11-Final.pdf "Cayman demonstrates RIDL potential"]. ''Oxitec Newsletter'', March 2011. Retrieved 20 September 2011</ref><ref name="Knapton" /> Another approach is to use a [[sterile insect technique]], whereby males genetically engineered to be sterile out compete viable males, to reduce population numbers.<ref>{{cite journal | vauthors = Benedict MQ, Robinson AS | title = The first releases of transgenic mosquitoes: an argument for the sterile insect technique | journal = Trends in Parasitology | volume = 19 | issue = 8 | pages = 349–55 | date = August 2003 | pmid = 12901936 | doi = 10.1016/s1471-4922(03)00144-2 }}</ref>

Other insect pests that make attractive targets are [[moth]]s. [[Diamondback moth]]s cause US$4 to $5 billion of damage each year worldwide.<ref name=":15">{{Cite web|url=https://www.theatlantic.com/science/archive/2017/09/genetically-modified-sterile-insects-take-flight/539040/|title=Genetically Modified Moths Come to New York| vauthors = Zhang S |date=8 September 2017|website=The Atlantic|access-date=23 December 2018}}</ref> The approach is similar to the sterile technique tested on mosquitoes, where males are transformed with a gene that prevents any females born from reaching maturity.<ref>{{Cite web|url=http://blogs.discovermagazine.com/d-brief/2017/05/10/genetic-engineering-moths/|title=After Mosquitos, Moths Are the Next Target For Genetic Engineering|vauthors=Scharping N|date=10 May 2017|website=[[Discover (magazine)|Discover]]|access-date=23 December 2018|archive-date=11 November 2019|archive-url=https://web.archive.org/web/20191111080853/http://blogs.discovermagazine.com/d-brief/2017/05/10/genetic-engineering-moths/|url-status=dead}}</ref> They underwent field trials in 2017.<ref name=":15" /> Genetically modified moths have previously been released in field trials.<ref>{{cite journal | vauthors = Reeves R, Phillipson M |date = January 2017 |title = Mass Releases of Genetically Modified Insects in Area-Wide Pest Control Programs and Their Impact on Organic Farmers |journal=Sustainability|volume=9|issue=1|pages=59|doi=10.3390/su9010059 |doi-access=free|bibcode = 2017Sust....9...59R }}</ref> In this case a strain of [[pink bollworm]] that were sterilized with radiation were genetically engineered to express a [[Green fluorescent protein|red fluorescent protein]] making it easier for researchers to monitor them.<ref>{{cite journal | vauthors = Simmons GS, McKemey AR, Morrison NI, O'Connell S, Tabashnik BE, Claus J, Fu G, Tang G, Sledge M, Walker AS, Phillips CE, Miller ED, Rose RI, Staten RT, Donnelly CA, Alphey L | title = Field performance of a genetically engineered strain of pink bollworm | journal = PLOS ONE | volume = 6 | issue = 9 | pages = e24110 | date = 13 September 2011 | pmid = 21931649 | pmc = 3172240 | doi = 10.1371/journal.pone.0024110 | bibcode = 2011PLoSO...624110S | doi-access = free }}</ref>

Silkworm, the larvae stage of ''[[Bombyx mori]]'', is an economically important insect in [[sericulture]]. Scientists are developing strategies to enhance silk quality and quantity. There is also potential to use the silk producing machinery to make other valuable proteins.<ref>{{cite journal | vauthors = Xu H, O'Brochta DA | title = Advanced technologies for genetically manipulating the silkworm Bombyx mori, a model Lepidopteran insect | journal = Proceedings. Biological Sciences | volume = 282 | issue = 1810 | date = July 2015 | pmid = 26108630 | pmc = 4590473 | doi = 10.1098/rspb.2015.0487 | page=20150487}}</ref> Proteins currently developed to be expressed by silkworms include; [[human serum albumin]], [[Collagen alpha-1(IV) chain|human collagen α-chain]], mouse [[monoclonal antibody]] and [[NGLY1|N-glycanase]].<ref>{{cite journal | vauthors = Tomita M | title = Transgenic silkworms that weave recombinant proteins into silk cocoons | journal = Biotechnology Letters | volume = 33 | issue = 4 | pages = 645–54 | date = April 2011 | pmid = 21184136 | doi = 10.1007/s10529-010-0498-z | s2cid = 25310446 }}</ref> Silkworms have been created that produce [[spider silk]], a stronger but extremely difficult to harvest silk,<ref>{{cite journal | vauthors = Xu J, Dong Q, Yu Y, Niu B, Ji D, Li M, Huang Y, Chen X, Tan A | title = Bombyx mori | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 115 | issue = 35 | pages = 8757–8762 | date = August 2018 | pmid = 30082397 | pmc = 6126722 | doi = 10.1073/pnas.1806805115 | doi-access = free }}</ref> and even novel silks.<ref>{{cite web |url= https://www.newscientist.com/article/2165351-gm-worms-make-a-super-silk-completely-unknown-in-nature/ |title= GM worms make a super-silk completely unknown in nature| vauthors = Le Page M |website=New Scientist |access-date=23 December 2018}}</ref>

=== Other ===
[[File:Frog GFP eye.gif|thumb|upright|Frog expressing [[green fluorescent protein]]|alt=|left]]
Systems have been developed to create transgenic organisms in a wide variety of other animals. Chickens have been genetically modified for a variety of purposes. This includes studying [[embryo development]],<ref>{{Cite web|url=https://projects.ncsu.edu/cals/agcomm/magazine/spring03/transgenic.htm|title=Poultry scientists develop transgenic chicken to aid study of embryo development|website=[[North Carolina State University]]|access-date=23 December 2018}}</ref> preventing the transmission of [[Bird-flu|bird flu]]<ref>{{Cite web|url=https://www.sciencedaily.com/releases/2011/01/110113141601.htm|title=Genetically modified chickens that don't transmit bird flu developed; Breakthrough could prevent future bird flu epidemics|website=ScienceDaily|access-date=23 December 2018}}</ref> and providing evolutionary insights using [[reverse engineering]] to recreate dinosaur-like phenotypes.<ref>{{cite journal | vauthors = Botelho JF, Smith-Paredes D, Soto-Acuña S, O'Connor J, Palma V, Vargas AO | title = Molecular development of fibular reduction in birds and its evolution from dinosaurs | journal = Evolution; International Journal of Organic Evolution | volume = 70 | issue = 3 | pages = 543–54 | date = March 2016 | pmid = 26888088 | pmc = 5069580 | doi = 10.1111/evo.12882 }}</ref> A GM chicken that produces the drug [[Kanuma (drug)|Kanuma]], an enzyme that treats a rare condition, in its egg passed US regulatory approval in 2015.<ref>{{cite journal | vauthors = Becker R |title=US government approves transgenic chicken |journal=Nature |date=9 December 2015 |doi=10.1038/nature.2015.18985 |doi-access=free }}</ref> Genetically modified frogs, in particular ''[[African clawed frog|Xenopus laevis]]'' and ''[[Western clawed frog|Xenopus tropicalis]]'', are used in [[Development (biology)|developmental biology]] research. GM frogs can also be used as pollution sensors, especially for [[Endocrine disruptor|endocrine disrupting chemicals]].<ref>{{cite journal | vauthors = Fini JB, Le Mevel S, Turque N, Palmier K, Zalko D, Cravedi JP, Demeneix BA | title = An in vivo multiwell-based fluorescent screen for monitoring vertebrate thyroid hormone disruption | journal = Environmental Science & Technology | volume = 41 | issue = 16 | pages = 5908–14 | date = August 2007 | pmid = 17874805 | doi = 10.1021/es0704129 | bibcode = 2007EnST...41.5908F }}</ref> There are proposals to use genetic engineering to control [[cane toads in Australia]].<ref>{{Cite web|url=http://sitn.hms.harvard.edu/flash/2014/removing-threat-from-invasive-species-with-genetic-engineering/|title=Removing Threat from Invasive Species with Genetic Engineering?|date=28 July 2014|website=Science in the News|access-date=23 December 2018|archive-date=23 December 2018|archive-url=https://web.archive.org/web/20181223121003/http://sitn.hms.harvard.edu/flash/2014/removing-threat-from-invasive-species-with-genetic-engineering/|url-status=dead}}</ref><ref>{{Cite web|url=https://www.abc.net.au/radionational/programs/scienceshow/cane-toads-to-get-the-crispr-treatment/9161942|title=Cane toads to get the Crispr treatment|date=17 November 2017|website=Radio National |access-date=23 December 2018}}</ref>

The [[nematode]] ''[[Caenorhabditis elegans]]'' is one of the major model organisms for researching [[molecular biology]].<ref>{{Cite web|url=http://www.wormbook.org/chapters/www_nematodeshistory/nematodeshistory.html|title=History of research on ''C. elegans'' and other free-living nematodes as model organisms|website=www.wormbook.org|access-date=24 December 2018}}</ref> [[RNA interference]] (RNAi) was discovered in ''C. elegans''<ref>{{Cite journal | vauthors = Hopkin M |date=2 October 2006 |title=RNAi scoops medical Nobel |journal= Nature News |doi=10.1038/news061002-2 |s2cid=85168270 }}</ref> and could be induced by simply feeding them bacteria modified to express [[Double-stranded RNA|double stranded RNA]].<ref>{{cite journal | vauthors = Conte D, MacNeil LT, Walhout AJ, Mello CC | title = RNA Interference in ''Caenorhabditis elegans'' | journal = Current Protocols in Molecular Biology | volume = 109 | pages = 26.3.1–30 | date = January 2015 | pmid = 25559107 | pmc = 5396541 | doi = 10.1002/0471142727.mb2603s109 }}</ref> It is also relatively easy to produce stable transgenic nematodes and this along with RNAi are the major tools used in studying their genes.<ref name=":16">{{cite book | vauthors = Praitis V, Maduro MF | title = Transgenesis in ''C. elegans'' | 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 = 9780125441728 }}</ref> The most common use of transgenic nematodes has been studying gene expression and localization by attaching reporter genes. Transgenes can also be combined with RNAi techniques to rescue phenotypes, study gene function, image cell development in real time or control expression for different tissues or developmental stages.<ref name=":16" /> Transgenic nematodes have been used to study viruses,<ref>{{cite journal | vauthors = Diogo J, Bratanich A | title = The nematode ''Caenorhabditis elegans'' as a model to study viruses | journal = Archives of Virology | volume = 159 | issue = 11 | pages = 2843–51 | date = November 2014 | pmid = 25000902 | doi = 10.1007/s00705-014-2168-2 | s2cid = 254052063 | doi-access = free }}</ref> toxicology,<ref>{{cite book | vauthors = Tejeda-Benitez L, Olivero-Verbel J | title = Reviews of Environmental Contamination and Toxicology Volume 237 | chapter = Caenorhabditis elegans, a Biological Model for Research in Toxicology | journal = Reviews of Environmental Contamination and Toxicology | volume = 237 | pages = 1–35 | date = 2016 | pmid = 26613986 | doi = 10.1007/978-3-319-23573-8_1 | isbn = 978-3-319-23572-1 }}</ref> diseases,<ref>{{cite book | vauthors = Schmidt J, Schmidt T | title = Polyglutamine Disorders | chapter = Animal Models of Machado-Joseph Disease | series = Advances in Experimental Medicine and Biology | volume = 1049 | pages = 289–308 | date = 2018 | pmid = 29427110 | doi = 10.1007/978-3-319-71779-1_15 | isbn = 978-3-319-71778-4 }}</ref><ref>{{cite journal | vauthors = Griffin EF, Caldwell KA, Caldwell GA | title = Genetic and Pharmacological Discovery for Alzheimer's Disease Using ''Caenorhabditis elegans'' | journal = ACS Chemical Neuroscience | volume = 8 | issue = 12 | pages = 2596–2606 | date = December 2017 | pmid = 29022701 | doi = 10.1021/acschemneuro.7b00361 }}</ref> and to detect environmental pollutants.<ref>{{cite book | vauthors = Daniells C, Mutwakil MH, Power RS, David HE, De Pomerai DI | chapter =Transgenic Nematodes as Biosensors of Environmental Stress|date=2002|chapter-url=https://link.springer.com/chapter/10.1007/978-94-010-0357-5_15|title =Biotechnology for the Environment: Strategy and Fundamentals|pages=221–236|series=Focus on Biotechnology| volume =3A|publisher=Springer, Dordrecht |doi=10.1007/978-94-010-0357-5_15|isbn=9789401039079|access-date=24 December 2018}}</ref>

[[File:Transgenic hydra endo.gif|thumb|upright|Transgenic Hydra expressing green fluorescent protein]]

The gene responsible for [[albinism]] in [[sea cucumber]]s has been found and used to engineer [[white sea cucumber]]s, a rare delicacy. The technology also opens the way to investigate the genes responsible for some of the cucumbers more unusual traits, including [[Hibernation|hibernating]] in summer, [[Evisceration (autotomy)|eviscerating]] their intestines, and dissolving their bodies upon death.<ref>{{Cite web|url=https://www.scmp.com/tech/science-research/article/1846481/more-valuable-gold-not-long-genetically-modified-sea-cucumbers|title=More valuable than gold, but not for long: genetically-modified sea cucumbers headed to China's dinner tables|date=5 August 2015|website=South China Morning Post|access-date=23 December 2018}}</ref> [[Flatworm]]s have the ability to regenerate themselves from a single cell.<ref name="pmid29906446">{{cite journal | vauthors = Zeng A, Li H, Guo L, Gao X, McKinney S, Wang Y, Yu Z, Park J, Semerad C, Ross E, Cheng LC, Davies E, Lei K, Wang W, Perera A, Hall K, Peak A, Box A, Sánchez Alvarado A | display-authors = 6| title = Prospectively Isolated Tetraspanin+ Neoblasts Are Adult Pluripotent Stem Cells Underlying Planaria Regeneration | journal = Cell | volume = 173 | issue = 7 | pages = 1593–1608.e20 | date = June 2018 | pmid = 29906446 | doi = 10.1016/j.cell.2018.05.006 | pmc = 9359418| doi-access = free}}
*{{cite journal |date=14 June 2018 |title=One special cell can revive a flatworm on the brink of death |journal=Nature |volume=558 |issue=7710 |pages=346–347 |doi=10.1038/d41586-018-05440-2 |bibcode=2018Natur.558S.346. |s2cid=256768390 |url=http://www.nature.com/articles/d41586-018-05440-2 |url-access=subscription}}</ref> Until 2017 there was no effective way to transform them, which hampered research. By using microinjection and radiation scientists have now created the first genetically modified flatworms.<ref>{{cite journal | vauthors = Wudarski J, Simanov D, Ustyantsev K, de Mulder K, Grelling M, Grudniewska M, Beltman F, Glazenburg L, Demircan T, Wunderer J, Qi W, Vizoso DB, Weissert PM, Olivieri D, Mouton S, Guryev V, Aboobaker A, Schärer L, Ladurner P, Berezikov E | title = Efficient transgenesis and annotated genome sequence of the regenerative flatworm model Macrostomum lignano | journal = Nature Communications | volume = 8 | issue = 1 | pages = 2120 | date = December 2017 | doi = 10.1038/s41467-017-02214-8 | pmid = 29242515 | pmc = 5730564 | bibcode = 2017NatCo...8.2120W }}</ref> The [[bristle worm]], a marine [[annelid]], has been modified. It is of interest due to its reproductive cycle being synchronized with lunar phases, regeneration capacity and slow evolution rate.<ref>{{cite journal | vauthors = Zantke J, Bannister S, Rajan VB, Raible F, Tessmar-Raible K | title = Genetic and genomic tools for the marine annelid Platynereis dumerilii | journal = Genetics | volume = 197 | issue = 1 | pages = 19–31 | date = May 2014 | pmid = 24807110 | doi = 10.1534/genetics.112.148254 | pmc=4012478}}</ref> [[Cnidarians|Cnidaria]] such as ''[[Hydra (genus)|Hydra]]'' and the sea anemone ''[[Starlet sea anemone|Nematostella vectensis]]'' are attractive model organisms to study the evolution of [[immunity (medical)|immunity]] and certain developmental processes.<ref>{{cite journal|vauthors=Wittlieb J, Khalturin K, Lohmann JU, Anton-Erxleben F, Bosch TC|date=April 2006|title=Transgenic Hydra allow in vivo tracking of individual stem cells during morphogenesis |journal=Proceedings of the National Academy of Sciences of the United States of America |volume=103 |issue=16 |pages=6208–11 |bibcode=2006PNAS..103.6208W |doi=10.1073/pnas.0510163103 |pmc=1458856|pmid=16556723 |doi-access=free }}</ref> Other animals that have been genetically modified include [[snail]]s,<ref name="pmid25529990">{{cite journal | vauthors = Perry KJ, Henry JQ | title = CRISPR/Cas9-mediated genome modification in the mollusc, Crepidula fornicata | journal = Genesis | volume = 53 | issue = 2 | pages = 237–44 | date = February 2015 | pmid = 25529990 | doi = 10.1002/dvg.22843 | s2cid = 36057310 }}</ref> [[gecko]]s, [[turtle]]s,<ref>{{cite journal | vauthors = Nomura T, Yamashita W, Gotoh H, Ono K | title = Genetic manipulation of reptilian embryos: toward an understanding of cortical development and evolution | journal = Frontiers in Neuroscience | volume = 9 | pages = 45 | date = 24 February 2015 | pmid = 25759636 | pmc = 4338674 | doi = 10.3389/fnins.2015.00045 | doi-access = free }}</ref> [[crayfish]], [[oyster]]s, [[shrimp]], [[clam]]s, [[abalone]]<ref>{{Cite journal| vauthors = Rasmussen RS, Morrissey MT |date=2007|title=Biotechnology in Aquaculture: Transgenics and Polyploidy |journal=Comprehensive Reviews in Food Science and Food Safety |volume=6|issue=1|pages=2–16|doi=10.1111/j.1541-4337.2007.00013.x }}</ref> and [[sponge]]s.<ref>{{cite journal | vauthors = Ebert MS, Sharp PA | title = MicroRNA sponges: progress and possibilities | journal = RNA | volume = 16 | issue = 11 | pages = 2043–50 | date = November 2010 | pmid = 20855538 | pmc = 2957044 | doi = 10.1261/rna.2414110 }}</ref>