Editing Genetically modified organism (section)

=== Crops ===

{{Main|Genetically modified crops}}{{See also|Genetically modified food}}
[[File:Bt plants.png|thumb|upright|Wild type peanut ('''top''') and transgenic peanut with ''[[Bacillus thuringiensis]]'' gene added ('''bottom''') exposed to [[Elasmopalpus|cornstalk borer larva]]|alt=]]
Genetically modified crops are genetically modified plants that are used in [[agriculture]]. The first crops developed were used for animal or human food and provide resistance to certain pests, diseases, environmental conditions, spoilage or chemical treatments (e.g. resistance to a [[herbicide]]). The second generation of crops aimed to improve the quality, often by altering the [[Nutrient profiling|nutrient profile]]. Third generation genetically modified crops could be used for non-food purposes, including the production of [[Plant manufactured pharmaceuticals|pharmaceutical agents]], [[biofuels]], and other industrially useful goods, as well as for [[bioremediation]].<ref name=":12">{{cite book|title=Genetically Modified Crops and Agricultural Development| vauthors = Qaim M |date=29 April 2016|publisher=Springer|isbn=978-1-137-40572-2|pages=1–10|chapter=Introduction}}</ref>

[[File:Btcornafrica.jpg|thumb | Kenyans examining insect-resistant transgenic [[Bt corn|''Bacillus thuringiensis'' (Bt) corn]]|alt=|left]]

There are three main aims to agricultural advancement; increased production, improved conditions for agricultural workers and [[sustainability]]. GM crops contribute by improving harvests through reducing insect pressure, increasing nutrient value and tolerating different [[abiotic stress]]es. Despite this potential, as of 2018, the commercialized crops are limited mostly to [[cash crop]]s like cotton, soybean, maize and canola and the vast majority of the introduced traits provide either herbicide tolerance or insect resistance.<ref name=":12" /> Soybeans accounted for half of all genetically modified crops planted in 2014.<ref name="isaaa2">{{cite web|url=http://www.isaaa.org/resources/publications/briefs/49/default.asp|title=Global Status of Commercialized Biotech/GM Crops: 2014 – ISAAA Brief 49-2014|publisher=ISAAA.org|access-date=15 September 2016}}</ref> Adoption by farmers has been rapid, between 1996 and 2013, the total surface area of land cultivated with GM crops increased by a factor of 100.<ref name="James2013">ISAAA 2013 Annual Report [http://www.isaaa.org/resources/publications/briefs/46/executivesummary/ Executive Summary, Global Status of Commercialized Biotech/GM Crops: 2013] ISAAA Brief 46-2013, Retrieved 6 August 2014</ref> Geographically though the spread has been uneven, with strong growth in the [[Americas]] and parts of Asia and little in Europe and Africa.<ref name=":12" /> Its [[Socioeconomics|socioeconomic]] spread has been more even, with approximately 54% of worldwide GM crops grown in [[Developing country|developing countries]] in 2013.<ref name="James2013" /> Although doubts have been raised,<ref>{{Cite news|url=https://www.nytimes.com/2016/10/30/business/gmo-promise-falls-short.html |archive-url=https://ghostarchive.org/archive/20220102/https://www.nytimes.com/2016/10/30/business/gmo-promise-falls-short.html |archive-date=2 January 2022 |url-access=limited |url-status=live|title=Doubts About the Promised Bounty of Genetically Modified Crops| vauthors = Hakim D |date=29 October 2016|work=The New York Times|access-date=5 May 2017|issn=0362-4331}}{{cbignore}}</ref> most studies have found growing GM crops to be beneficial to farmers through decreased pesticide use as well as increased crop yield and farm profit.<ref>{{Cite journal|vauthors=Areal FJ, Riesgo L, Rodríguez-Cerezo E|date=February 2013|title=Economic and agronomic impact of commercialized GM crops: a meta-analysis|journal=The Journal of Agricultural Science|volume=151|issue=1|pages=7–33|doi=10.1017/S0021859612000111|s2cid=85891950 |issn=0021-8596}}</ref><ref>{{cite journal | vauthors = Finger R, El Benni N, Kaphengst T, Evans C, Herbert S, Lehmann B, Morse S, Stupak N | display-authors = 6 |title=A Meta Analysis on Farm-Level Costs and Benefits of GM Crops |journal=Sustainability |date=10 May 2011 |volume=3 |issue=5 |pages=743–762 |doi=10.3390/su3050743 |doi-access=free | bibcode = 2011Sust....3..743F |hdl=20.500.11850/42242 |hdl-access=free }}</ref><ref>{{cite journal|vauthors=Klümper W, Qaim M|date=3 November 2014|title=A meta-analysis of the impacts of genetically modified crops|journal=PLOS ONE|volume=9|issue=11|pages=e111629|bibcode=2014PLoSO...9k1629K|doi=10.1371/journal.pone.0111629|pmc=4218791|pmid=25365303 |doi-access=free }}</ref>

The majority of GM crops have been modified to be resistant to selected herbicides, usually a [[glyphosate]] or [[glufosinate]] based one. Genetically modified crops engineered to resist herbicides are now more available than conventionally bred resistant varieties;<ref name=":03">{{cite journal | vauthors = Darmency H | title = Pleiotropic effects of herbicide-resistance genes on crop yield: a review | journal = Pest Management Science | volume = 69 | issue = 8 | pages = 897–904 | date = August 2013 | pmid = 23457026 | doi = 10.1002/ps.3522 }}</ref> in the USA 93% of soybeans and most of the GM maize grown is glyphosate tolerant.<ref>{{cite journal | vauthors = Green JM | title = Current state of herbicides in herbicide-resistant crops | journal = Pest Management Science | volume = 70 | issue = 9 | pages = 1351–7 | date = September 2014 | doi = 10.1002/ps.3727 | pmid = 24446395 }}</ref> Most currently available genes used to engineer insect resistance come from the ''[[Bacillus thuringiensis]]'' bacterium and code for [[delta endotoxin]]s. A few use the genes that encode for [[vegetative insecticidal protein]]s.<ref>{{cite book |doi=10.1007/978-3-319-06892-3_10 |chapter=Sustainable Management of Insect-Resistant Crops |title=Plant Biotechnology |pages=115–127 |year=2014 | vauthors = Fleischer SJ, Hutchison WD, Naranjo SE |isbn=978-3-319-06891-6 }}</ref> The only gene commercially used to provide insect protection that does not originate from ''B. thuringiensis'' is the [[Cowpea]] [[trypsin inhibitor]] (CpTI). CpTI was first approved for use cotton in 1999 and is currently undergoing trials in rice.<ref>{{cite web |url= http://www.isaaa.org/gmapprovaldatabase/event/default.asp?EventID=78&Event=SGK321 |title=SGK321 | work = GM Approval Database | publisher = ISAAA.org |access-date=27 April 2017}}</ref><ref name="Qiu_2008">{{cite journal | vauthors = Qiu J | title = Is China ready for GM rice? | journal = Nature | volume = 455 | issue = 7215 | pages = 850–2 | date = October 2008 | pmid = 18923484 | doi = 10.1038/455850a | doi-access = free }}</ref> Less than one percent of GM crops contained other traits, which include providing virus resistance, delaying senescence and altering the plants composition.<ref name="isaaa2" />
[[File:Golden Rice.jpg|left|thumb|[[Golden rice]] compared to white rice]]
[[Golden rice]] is the most well known GM crop that is aimed at increasing nutrient value. It has been engineered with three genes that [[biosynthesis]]e [[beta-carotene]], a precursor of [[Retinol|vitamin A]], in the edible parts of rice.<ref name="ye2000">{{cite journal | vauthors = Ye X, Al-Babili S, Klöti A, Zhang J, Lucca P, Beyer P, Potrykus I | title = Engineering the provitamin A (beta-carotene) biosynthetic pathway into (carotenoid-free) rice endosperm | journal = Science | volume = 287 | issue = 5451 | pages = 303–5 | date = January 2000 | pmid = 10634784 | doi = 10.1126/science.287.5451.303 | bibcode = 2000Sci...287..303Y | s2cid = 40258379 }}</ref> It is intended to produce a fortified food to be grown and consumed in areas with a [[Vitamin A deficiency|shortage of dietary vitamin A]],<ref>{{cite web | title = 'Green revolution' hero | quote = One existing crop, genetically engineered 'golden rice' that produces vitamin A, already holds enormous promise for reducing blindness and dwarfism that result from a vitamin-A deficient diet. | vauthors  = Frist B | work = [[The Washington Times]]| date = 21 November 2006 | url = http://www.washtimes.com/commentary/20061120-094716-8709r.htm }}</ref> a deficiency which each year is estimated to kill 670,000 children under the age of 5<ref>{{cite journal | vauthors = Black RE, Allen LH, Bhutta ZA, Caulfield LE, de Onis M, Ezzati M, Mathers C, Rivera J | title = Maternal and child undernutrition: global and regional exposures and health consequences | journal = Lancet | volume = 371 | issue = 9608 | pages = 243–60 | date = January 2008 | pmid = 18207566 | doi = 10.1016/S0140-6736(07)61690-0 | author9 = Maternal Child Undernutrition Study Group | s2cid = 3910132 }}</ref> and cause an additional 500,000 cases of irreversible childhood blindness.<ref name="humphery1992">{{cite journal | vauthors = Humphrey JH, West KP, Sommer A | title = Vitamin A deficiency and attributable mortality among under-5-year-olds | journal = Bulletin of the World Health Organization | volume = 70 | issue = 2 | pages = 225–32 | date = 1992 | pmid = 1600583 | pmc = 2393289 }}</ref> The original golden rice produced 1.6μg/g of the [[carotenoid]]s, with further development increasing this 23 times.<ref name="paine2005">{{cite journal | vauthors = Paine JA, Shipton CA, Chaggar S, Howells RM, Kennedy MJ, Vernon G, Wright SY, Hinchliffe E, Adams JL, Silverstone AL, Drake R | title = Improving the nutritional value of Golden Rice through increased pro-vitamin A content | journal = Nature Biotechnology | volume = 23 | issue = 4 | pages = 482–7 | date = April 2005 | pmid = 15793573 | doi = 10.1038/nbt1082 | s2cid = 632005 }}</ref> It gained its first approvals for use as food in 2018.<ref name="GR2E">{{cite web |url= https://geneticliteracyproject.org/2018/05/29/us-fda-approves-gmo-golden-rice-as-safe-to-eat/ |title= US FDA approves GMO Golden Rice as safe to eat | work = Genetic Literacy Project |access-date=30 May 2018|date= 29 May 2018 }}</ref>

Plants and plant cells have been genetically engineered for production of [[biopharmaceutical]]s in [[bioreactors]], a process known as [[Pharming (genetics)|pharming]]. Work has been done with [[Lemna|duckweed]] ''[[Lemna minor]]'',<ref>{{cite journal | vauthors = Gasdaska JR, Spencer D, Dickey L | title = Advantages of Therapeutic Protein Production in the Aquatic Plant ''Lemna'' | journal = BioProcessing Journal | date = March 2003 | volume = 2 | issue = 2 | pages = 49–56 | doi = 10.12665/J22.Gasdaska | url = http://www.bioprocessingjournal.com/bioprocessingjournal.com/index.php/article-downloads/329-j22-advantages-of-therapeutic-protein-production-in-the-aquatic-plant-lemna }}{{Dead link|date=May 2023 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> the [[algae]] ''[[Chlamydomonas reinhardtii]]''<ref>(10 December 2012) [http://phys.org/news/2012-12-algae-complex-anti-cancer-drug.html "Engineering algae to make complex anti-cancer 'designer' drug"]. ''PhysOrg'', Retrieved 15 April 2013</ref> and the [[moss]] ''[[Physcomitrella patens]]''.<ref>{{cite journal | vauthors = Büttner-Mainik A, Parsons J, Jérôme H, Hartmann A, Lamer S, Schaaf A, Schlosser A, Zipfel PF, Reski R, Decker EL | title = Production of biologically active recombinant human factor H in Physcomitrella | journal = Plant Biotechnology Journal | volume = 9 | issue = 3 | pages = 373–83 | date = April 2011 | pmid = 20723134 | doi = 10.1111/j.1467-7652.2010.00552.x | doi-access = free | bibcode = 2011PBioJ...9..373B }}</ref><ref>{{cite journal | vauthors = Baur A, Reski R, Gorr G | title = Enhanced recovery of a secreted recombinant human growth factor using stabilizing additives and by co-expression of human serum albumin in the moss Physcomitrella patens | journal = Plant Biotechnology Journal | volume = 3 | issue = 3 | pages = 331–40 | date = May 2005 | pmid = 17129315 | doi = 10.1111/j.1467-7652.2005.00127.x | doi-access =  | bibcode = 2005PBioJ...3..331B }}</ref> Biopharmaceuticals produced include [[cytokine]]s, [[hormone]]s, [[Antibody|antibodies]], [[enzyme]]s and vaccines, most of which are accumulated in the plant seeds. Many drugs also contain natural plant ingredients and the pathways that lead to their production have been genetically altered or transferred to other plant species to produce greater volume.<ref name=":11">{{cite book|title=Plant Biotechnology: New Products and Applications|vauthors=Hammond J, McGarvey P, Yusibov V|date=6 December 2012|publisher=Springer Science & Business Media|isbn=978-3-642-60234-4|pages=7–8}}</ref> Other options for bioreactors are [[biopolymer]]s<ref>{{cite journal | vauthors = Börnke F, Broer I | title = Tailoring plant metabolism for the production of novel polymers and platform chemicals | journal = Current Opinion in Plant Biology | volume = 13 | issue = 3 | pages = 354–62 | date = June 2010 | pmid = 20171137 | doi = 10.1016/j.pbi.2010.01.005 | bibcode = 2010COPB...13..353B }}</ref> and [[biofuel]]s.<ref>{{cite journal | vauthors = Lehr F, Posten C | title = Closed photo-bioreactors as tools for biofuel production | journal = Current Opinion in Biotechnology | volume = 20 | issue = 3 | pages = 280–5 | date = June 2009 | pmid = 19501503 | doi = 10.1016/j.copbio.2009.04.004 }}</ref> Unlike bacteria, plants can [[Post-translational modification|modify the proteins post-translationally]], allowing them to make more complex molecules. They also pose less risk of being contaminated.<ref>{{cite web|url=http://agbiosafety.unl.edu/biopharm.shtml|title=UNL's AgBiosafety for Educators|website=agbiosafety.unl.edu|access-date=18 December 2018}}</ref> Therapeutics have been cultured in transgenic carrot and tobacco cells,<ref>{{Cite web|url=http://protalix.com/technology/procellex-platform/|archive-url=https://web.archive.org/web/20121027101102/http://protalix.com/procellex-platform/overview-procellex-platform.asp|url-status=dead|title=ProCellEx® Platform|archive-date=27 October 2012|website=Protalix Biotherapeutics}}</ref> including a drug treatment for [[Gaucher's disease]].<ref>Gali Weinreb and Koby Yeshayahou for Globes 2 May 2012. [http://www.globes.co.il/serveen/globes/docview.asp?did=1000745325&fid=1725 "FDA approves Protalix Gaucher treatment"]. {{webarchive|url=https://web.archive.org/web/20130529030847/http://www.globes.co.il/serveen/globes/docview.asp?did=1000745325&fid=1725|date=29 May 2013}}</ref>

Vaccine production and storage has great potential in transgenic plants. Vaccines are expensive to produce, transport, and administer, so having a system that could produce them locally would allow greater access to poorer and developing areas.<ref name=":11" /> As well as purifying vaccines expressed in plants it is also possible to produce edible vaccines in plants. Edible vaccines stimulate the [[immune system]] when ingested to protect against certain diseases. Being stored in plants reduces the long-term cost as they can be disseminated without the need for cold storage, don't need to be purified, and have long term stability. Also being housed within plant cells provides some protection from the gut acids upon digestion. However the cost of developing, regulating, and containing transgenic plants is high, leading to most current plant-based vaccine development being applied to [[veterinary medicine]], where the controls are not as strict.<ref>{{cite journal | vauthors = Concha C, Cañas R, Macuer J, Torres MJ, Herrada AA, Jamett F, Ibáñez C | title = Disease Prevention: An Opportunity to Expand Edible Plant-Based Vaccines? | journal = Vaccines | volume = 5 | issue = 2 | pages = 14 | date = May 2017 | pmid = 28556800 | pmc = 5492011 | doi = 10.3390/vaccines5020014 | doi-access = free }}</ref>

Genetically modified crops have been proposed as one of the ways to reduce farming-related {{CO2}} emissions due to higher yield, reduced use of pesticides, reduced use of tractor fuel and no tillage. According to a 2021 study, in EU alone widespread adoption of GE crops would reduce greenhouse gas emissions by 33 million tons of {{CO2}} equivalent or 7.5% of total farming-related emissions.<ref>{{Cite bioRxiv|date=10 February 2021|title=The climate benefits of yield increases in genetically engineered crops |biorxiv=10.1101/2021.02.10.430488 |last1=Kovak |first1=Emma |last2=Qaim |first2=Matin |last3=Blaustein-Rejto |first3=Dan}}</ref>