Editing Cannabis (section)

===Continuing research===
[[Molecular biology|Molecular analytical techniques]] developed in the late 20th century are being applied to questions of taxonomic classification. This has resulted in many reclassifications based on [[History of plant systematics#Evolutionary systematics|evolutionary systematics]]. Several studies of [[random amplified polymorphic DNA]] (RAPD) and other types of genetic markers have been conducted on drug and fiber strains of ''Cannabis'', primarily for [[plant breeding]] and forensic purposes.<ref name="faeti1996a">{{cite journal | vauthors = Mandolino G, Carboni A, Forapani S, Faeti V, Ranalli P |doi=10.1007/s001220051043|title=Identification of DNA markers linked to the male sex in dioecious hemp (Cannabis sativa L.)|year=1999 |journal=Theoretical and Applied Genetics|volume=98|pages=86–92|s2cid=26011527}}</ref><ref name="forapani2001a">{{cite journal|doi=10.2135/cropsci2001.1682|title=Comparison of Hemp Varieties Using Random Amplified Polymorphic DNA Markers|year=2001| vauthors = Forapani S, Carboni A, Paoletti C, Moliterni VM, Ranalli P, Mandolino G |s2cid=29448044|journal=Crop Science|volume=41|issue=6|page=1682|url=http://pdfs.semanticscholar.org/2e7d/f4b5dd7992dd5ad04d3098aae531fd2d7a28.pdf |archive-url=https://web.archive.org/web/20220311032503/http://pdfs.semanticscholar.org/2e7d/f4b5dd7992dd5ad04d3098aae531fd2d7a28.pdf |archive-date=2022-03-11 |url-status=live}}</ref><ref name="mandolino2002a">{{cite journal | vauthors = Mandolino G, Ranalli P |doi=10.1300/J237v07n01_03|title=The Applications of Molecular Markers in Genetics and Breeding of Hemp |year=2002 |journal=Journal of Industrial Hemp|volume=7|pages=7–23|s2cid=84960806}}</ref><ref name="gilmore2003a">{{cite journal | vauthors = Gilmore S, Peakall R, Robertson J | title = Short tandem repeat (STR) DNA markers are hypervariable and informative in Cannabis sativa: implications for forensic investigations | journal = Forensic Science International | volume = 131 | issue = 1 | pages = 65–74 | date = January 2003 | pmid = 12505473 | doi = 10.1016/S0379-0738(02)00397-3 }}</ref><ref name="kojoka2002a">{{cite journal | vauthors = Kojoma M, Iida O, Makino Y, Sekita S, Satake M | title = DNA fingerprinting of Cannabis sativa using inter-simple sequence repeat (ISSR) amplification | journal = Planta Medica | volume = 68 | issue = 1 | pages = 60–3 | date = January 2002 | pmid = 11842329 | doi = 10.1055/s-2002-19875 | bibcode = 2002PlMed..68...60K | s2cid = 260280872 }}</ref> Dutch ''Cannabis'' researcher E.P.M. de Meijer and coworkers described some of their RAPD studies as showing an "extremely high" degree of genetic polymorphism between and within populations, suggesting a high degree of potential variation for selection, even in heavily selected hemp cultivars.<ref name="meijer2003a"/> They also commented that these analyses confirm the continuity of the ''Cannabis'' [[gene pool]] throughout the studied accessions, and provide further confirmation that the genus consists of a single species, although theirs was not a systematic study ''per se''.

An investigation of genetic, morphological, and [[chemotaxonomic]] variation among 157 ''Cannabis'' accessions of known geographic origin, including fiber, drug, and feral populations showed cannabinoid variation in ''Cannabis'' [[germplasm]]. The patterns of cannabinoid variation support recognition of ''C.&nbsp;sativa'' and ''C.&nbsp;indica'' as separate species, but not ''C.&nbsp;ruderalis''. ''C.&nbsp;sativa'' contains fiber and seed landraces, and feral populations, derived from Europe, Central Asia, and [[Turkey]]. Narrow-leaflet and wide-leaflet drug accessions, southern and eastern Asian hemp accessions, and feral Himalayan populations were assigned to ''C.&nbsp;indica''.<ref name=hillig2004a/> In 2005, a [[Genetic testing|genetic analysis]] of the same set of accessions led to a three-species classification, recognizing ''C.&nbsp;sativa'', ''C.&nbsp;indica'', and (tentatively) ''C.&nbsp;ruderalis''.<ref name="hillig2005a"/> Another paper in the series on chemotaxonomic variation in the terpenoid content of the [[essential oil]] of ''Cannabis'' revealed that several wide-leaflet drug strains in the collection had relatively high levels of certain [[sesquiterpene]] alcohols, including [[guaiol]] and isomers of eudesmol, that set them apart from the other putative taxa.<ref name="hillig2004b">{{cite journal|doi=10.1016/j.bse.2004.04.004|title=A chemotaxonomic analysis of terpenoid variation in Cannabis|year=2004| vauthors = Hillig KW |journal=Biochemical Systematics and Ecology|volume=32|issue=10|pages=875–891|bibcode=2004BioSE..32..875H }}</ref><!--
As of 2007, taxonomy web sites continue to list ''Cannabis'' as a genus with a single species, whilst listing Cannabis Sativa, Cannabis Indica and Cannabis Ruderalis as subspecies.<ref name="GRIN">USDA, ARS, National Genetic Resources Program. [http://www.ars-grin.gov/cgi-bin/npgs/html/splist.pl?2034 Germplasm Resources Information Network (GRIN)], National Germplasm Resources Laboratory, Beltsville, Maryland. Retrieved on 23 February 2007</ref><ref name="APNI">Barlow, Snow. 2006. [http://www.plantnames.unimelb.edu.au/Sorting/Cannabis.html Sorting ''Cannabis'' names]. Multilingual Multiscript Plant Name Database. The University of Melbourne. Retrieved on 23 February 2007</ref><ref name="ITIS">[https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=19109 Integrated Taxonomic Information System (ITIS)]. Retrieved on 23 February 2007</ref><ref name="taxonomicon">[http://www.taxonomy.nl/Taxonomicon/TaxonTree.aspx?id=6455 The Taxonomicon]. Universal Taxonomic Services. Retrieved on 23 February 2007</ref>-->

A 2020 analysis of [[single-nucleotide polymorphism]]s reports five clusters of ''cannabis'', roughly corresponding to hemps (including folk "Ruderalis") folk "Indica" and folk "Sativa".<ref>{{cite journal | vauthors = Henry P, Khatodia S, Kapoor K, Gonzales B, Middleton A, Hong K, Hilyard A, Johnson S, Allen D, Chester Z, Jin D, Rodriguez Jule JC, Wilson I, Gangola M, Broome J, Caplan D, Adhikary D, Deyholos MK, Morgan M, Hall OW, Guppy BJ, Orser C | display-authors = 6 | title = A single nucleotide polymorphism assay sheds light on the extent and distribution of genetic diversity, population structure and functional basis of key traits in cultivated north American cannabis | journal = Journal of Cannabis Research | volume = 2 | issue = 1 | pages = 26 | date = September 2020 | pmid = 33526123 | pmc = 7819309 | doi = 10.1186/s42238-020-00036-y | doi-access = free }}</ref>

Despite advanced analytical techniques, much of the cannabis used recreationally is inaccurately classified. One laboratory at the [[University of British Columbia]] found that Jamaican Lamb's Bread, claimed to be 100% sativa, was in fact almost 100% indica (the opposite strain).<ref>{{cite news | vauthors = Ormiston S |date=17 January 2018 |title=What's in your weed: Why cannabis strains don't all live up to their billing |url=https://www.cbc.ca/news/thenational/ormiston-pot-marijuana-cannabis-weed-genetics-1.4489974 |work=CBC |access-date=2 October 2018 |archive-date=1 October 2018 |archive-url=https://web.archive.org/web/20181001142449/https://www.cbc.ca/news/thenational/ormiston-pot-marijuana-cannabis-weed-genetics-1.4489974 |url-status=live }} (Paper is {{PMID|26308334}}.)</ref> Legalization of cannabis in Canada ({{as of|2018|October|17|lc=y|df=}}) may help spur private-sector research, especially in terms of diversification of strains. It should also improve classification accuracy for cannabis used recreationally. Legalization coupled with Canadian government (Health Canada) oversight of production and labelling will likely result in more—and more accurate—testing to determine exact strains and content. Furthermore, the rise of craft cannabis growers in Canada should ensure quality, experimentation/research, and diversification of strains among private-sector producers.<ref>{{cite web |url=https://licensedproducerscanada.ca/faq/will-craft-cannabis-growers-in-canada-succeed-like-craft-brewers |title=Will Craft Cannabis Growers in Canada Succeed Like Craft Brewers? |author=<!--Not stated--> |date=<!--Not stated--> |website=Licensed Producers Canada |access-date=2 October 2018 |archive-date=8 May 2019 |archive-url=https://web.archive.org/web/20190508004314/https://licensedproducerscanada.ca/faq/will-craft-cannabis-growers-in-canada-succeed-like-craft-brewers |url-status=live }}</ref>