Genetic marker
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A genetic marker is an inherited difference at one position on a chromosome that can be scored in a plant and used to follow inheritance or to compare plants. It may be a visible character, a protein or a stretch of DNA; those read directly from DNA are also called DNA markers or molecular markers.[1] A marker reports its own state. It says something about a trait only where it lies in or close to a gene affecting that trait, in the plants under study.
In Cannabis sativa DNA markers date from the mid-1990s.[2] They have been used to tell the sex of seedlings, to predict chemotype, to separate hemp from drug-type cannabis and to identify plants and cultivars. The number of loci typed, the way they were chosen and the number of plants standing for each population set what a study can claim. An assay tested in a set of cultivars has been shown to work in those cultivars.
Tagging a trait and surveying a genome
A marker used as a tag has to sit near the gene it stands for. It may lie inside the gene or beside it on the chromosome. The closer the two lie, the less often recombination separates them. A marker absolutely linked to a gene co-segregates with the trait. Selecting on such a marker lets a breeder discard plants early, before flowering if need be, often at lower cost than scoring the trait itself.[1] Mapping a quantitative trait locus rests on the same linkage.
A survey uses many markers across the genome to fingerprint plants or to measure how variation is divided among them. The properties wanted are abundance, high polymorphism, reproducibility and selective neutrality.[1] Neutral markers have allowed conservation geneticists to assess genetic drift, inbreeding and gene flow.[3] In Cannabis genetic resources, Welling and colleagues cautioned, such markers "do not necessarily reflect quantitative patterns of trait variation" and cannot always be relied on to describe functional diversity.[4] In an early survey of accessions six of 45 seed-protein bands varied, and their patterns followed neither origin nor agronomic grouping nor expected common ancestry.[5]
Markers also differ in what they reveal of a heterozygote. A codominant marker tells it from both homozygotes and a dominant one does not, a distinction taken up under dominance and recessivity. A DNA marker shows what a plant carries and is unaffected by its environment; whether a linked allele gives the expected character depends on the environment and on other genes.[1]
Kinds of marker
| Kind | What is scored | Inheritance | What it can show | What limits it |
|---|---|---|---|---|
| Morphological | A visible character, such as yellow stem in hemp[6] | That of the character; yellow stem is recessive and follows one gene[6] | Segregation in a cross, scored by eye in large populations[6] | Few in number and affected by environment[1] |
| Allozyme | Forms of an enzyme separated by electrophoresis | Codominant[7] | Allele frequencies across accessions[8] | 17 loci in one large survey;[8] a band may fail to match the DNA sequence beneath it, and may be an artefact[4] |
| RAPD | DNA segments amplified with one short primer of arbitrary sequence, present or absent[9] | Dominant[10] | Polymorphism with no sequence known beforehand; a first screen for linked bands[11] | Difficult to reproduce between laboratories[12] |
| AFLP | Restriction fragments amplified selectively, 50 to 100 at a time on a gel[13] | Mainly dominant[14] | Hundreds of replicable bands[14] with no sequence known beforehand[13] | Anonymous loci, which may differ between populations[1] |
| Microsatellite (SSR, STR) | Length of a short tandem repeat, amplified with primers on either side[1] | Codominant[7] | Many alleles per locus; identity testing, population studies, linkage[15] | Few loci per run;[1] alleles of one length can differ in ancestry (homoplasy) and flanking mutations can stop an allele amplifying[16] |
| SNP | One base that differs between alleles[1] | Both alleles can be read; with no reference genome, sequence tags can be treated as dominant[17] | The most abundant polymorphism;[1] many sites at once through genotyping by sequencing or whole genomes | Results depend on the plants in which the SNPs were found[18] and on the filters applied |
Chloroplast and mitochondrial markers follow a separate line of descent. Chloroplast DNA does not recombine and is maternally inherited in most flowering plants, so it shows variation from the maternal parent only. Its diversity in Cannabis is low.[19] Haplotypes at 12 chloroplast and mitochondrial loci in 188 plants fell into three groups that were suggestive of crop use and geographic origin, "although not strictly diagnostic".[20]
What a set of markers can claim
In a compilation of 307 plant studies, microsatellites gave almost three times the within-population diversity of RAPD, AFLP and related dominant markers, with similar among-population values.[10] A figure therefore has to be read with its marker system. Published heterozygosity estimates in Cannabis vary with the markers used.
Microsatellite loci are usually chosen because they are highly polymorphic, a bias that can reduce their sensitivity to genome-wide diversity.[16] In eight carnivore populations nucleotide diversity varied 30-fold while microsatellite heterozygosity varied 1.4-fold. The two were correlated across populations (r2 0.70) and not significantly across individuals.[21] For the split between hemp and drug type, 13 microsatellite loci gave a picture concordant with high-density SNP data.[22] Six SNPs sufficed in silico to tell 32 cultivars apart. Genotyping at such low density proved limited for working out how the cultivars are related.[23]
In human data, SNPs on genotyping arrays tend to be older and shared among populations, which shifts allele frequencies towards intermediate values.[18] Filters remove further sites: a survey of hemp and drug-type samples dropped SNPs with a minor allele frequency below 1 per cent,[24] which removes rare variants before any analysis.
Some diversity estimates in plants correlate with the number of plants sampled per population. Among-population diversity rises with the distance between the populations sampled.[10] A survey of Iranian cannabis typed one female and one male plant from each location;[25] the organelle survey above averaged fewer than three plants per population.[20] A landrace parent in a mapping cross may be a single plant.[26]
Sex before flowering
Male and female plants look alike before flowering.[27] Sex and chemotype have been the main targets of markers in hemp breeding.[2] Early sex markers came from RAPD screening. MADC1 was a 730-base-pair fragment found in all male plants tested and in none of the females; as a probe, it gave intense male-specific bands along with fainter bands common to both sexes.[28] A 400-base-pair band from the primer OPA8 was associated with male plants in 14 hemp cultivars and accessions. Among 167 plants it was never missing from a male and never present in a monoecious plant, but three phenotypic females carried it, and the sequence itself was present in both sexes.[11] Such bands were then converted to sequence-characterised (SCAR) markers, which use primers specific to the band.[11][29][30]
Several of these markers lie in retrotransposons,[31] which some cultivars may lack.[32][27] Newer markers target genes that differ between the X and the Y. A multiplex of two Y-linked markers and one autosomal control sexed 191 of 192 plants from 12 hemp cultivars correctly; the remaining plant may have been mis-sexed or sex-reversed. In silico only one of the two Y markers matched the two male drug-type genomes available.[32] An assay using one primer pair was run on 14 hemp-type cultivars and checked against published genomes of other hemp and drug-type plants.[27] The validation of a high-throughput assay covered "a wide range of germplasm".[33]
A sex marker reads chromosomes. Monoecious plants are XX and score with females.[33][27] A plant's sex expression can still be changed by treatment such as silver nitrate, which brings male flowers on a plant that is genetically female.[27]
Chemotype
De Meijer and colleagues proposed a single locus, B, for the chemotype, screened RAPD primers on pooled DNA of F2 plants sorted by chemotype and converted one associated band into a codominant SCAR marker tightly linked to it.[34] Sequence differences in the gene for THCA synthase then gave a PCR marker found in six drug-type strains and absent from seven fibre-type strains,[35] and specific polymorphisms in that gene were found to be absolutely linked to chemotype in two segregating populations.[36] The inheritance behind these assays is set out under genetic traits.
Genotyping at the gene for CBDA synthase was tried on feral plants in Minnesota, on blinded samples of 20 clinical cultivars and on 12 Canadian grain cultivars. It predicted the ratio of tetrahydrocannabinol (THC) to cannabidiol (CBD) among the clinical cultivars. Among the grain cultivars it did so only where plants held more than 0.5 per cent total cannabinoids.[37] The high-throughput assay found that cultivar populations thought to be stabilised for CBD were segregating.[33] Markers that separate the THC and CBD types lie inside the B locus, and features outside it do not correlate with chemotype. Structural variation inside the locus means marker design has to account for more than one arrangement.[38]
A chemotype marker predicts a ratio. In the Minnesota plants genotype matched chemotype class in every plant, while total cannabinoid content ran from under 1 to over 10 per cent.[37] In the high-throughput study many plants producing predominantly CBD exceeded the US limit of 0.3 per cent THC by dry weight.[33]
Hemp, drug type and populations
Early DNA surveys in hemp used RAPD. About 200 fragments from 13 cultivars and accessions separated Italian from Hungarian germplasm and set a Korean group apart.[39] In six varieties, among them a dioecious landrace and a selection from it, heterozygosity tracked breeding history, from 0.05 in an inbred female line to 0.26 in a cross-bred cultivar.[40] From allele frequencies at 17 allozyme loci in 157 accessions, Hillig proposed three species.[8] Welling and colleagues called such taxonomic divisions controversial and questioned whether allozyme and chemical surveys are neutral measures of structure.[4]
Later studies differ on whether hemp and drug type can be told apart. They also used different numbers of markers and different plants.
| Study | Markers | Material | Result |
|---|---|---|---|
| Gilmore and colleagues 2003 | 5 microsatellites | 93 plants | 6 per cent of variation between crop types; plants could not be assigned unequivocally to drug or fibre[41] |
| Datwyler and Weiblen 2006 | AFLP, 1,206 bands | 3 fibre populations, 1 drug cultivar | 18 bands fixed between all fibre populations and the drug cultivar[42] |
| Sawler and colleagues 2015 | 14,031 SNPs | 43 hemp, 81 drug-type samples | Clear separation; no SNP fixed between the groups[24] |
| Lynch and colleagues 2016 | SNPs from sequencing | 339 varieties | At least three major groups[43] |
| Dufresnes and colleagues 2017 | 13 microsatellites | 1,324 plants of 39 varieties | Assignment to type correct in direct tests; many plants left unassigned by a conservative test[22] |
| Henry and colleagues 2020 | 23 selected SNPs | 420 North American samples | Five clusters, three of them drug-type groups differing in dominant terpenes[44] |
The 18 AFLP bands separate three fibre populations from one drug cultivar. The SNP survey compared 81 drug-type samples and found no fixed marker. The counts of groups above come from different markers, plants and clustering methods. They are not estimates of one quantity. The 23 SNPs were selected for their information content and for their association with traits such as cannabinoid and terpene expression.[44]
Landrace accessions were part of the allozyme survey. Accessions from Iran have since been typed by genotyping by sequencing[25] and, in a later panel, at about 233,000 variants.[45] Chloroplast markers have partitioned variation differently from nuclear markers, probably because they detect variation from the maternal parent only.[19] Assigning ancestry along chromosomes is covered under introgression.
Plants and cultivars
RAPD told apart all but two of 17 plants grown together, where cannabinoid analysis gave three groups.[46] With 11 microsatellites, 41 samples gave 27 profiles;[47] with five, all of 93 plants were unique except four from one drug-type accession.[41] Clones share a profile, so a profile can identify a line of clones and not one plant in it. Among drug varieties, some sold under different names were genetically identical and some under one name were distinct.[22]
A ten-locus microsatellite kit scored consistently from 1 to 10 nanograms of template DNA, with allelic dropout and failures below that.[48] Gilmore and colleagues had suggested that such markers could give the geographic origin of seizures,[41] yet six loci did not relate samples from the same US state in 98 plants from 33 states.[49] Clonal propagation and possible aneuploidy mean that statistics following the Hardy–Weinberg law cannot be applied to a 15-locus kit.[50] Assignment also needs a reference database that covers variation within and among varieties, and the drug varieties in circulation change quickly.[22]
Ten microsatellites developed from the Purple Kush genome, applied to 122 samples of 30 strains from dispensaries in three US states, divided the plants into two groups that did not match reported sativa and indica proportions. Most strains held at least one genetic outlier. Many looked stable once outliers were removed.[51] Six microsatellites typed in 20 drug-type cultivars and two hemp cultivars placed 32 per cent of the variation among cultivars and the remainder within them.[52] A 20-SNP panel for 32 cultivars called genotypes less often from dried flower than from fresh leaf, and its assays did not always agree with the sequencing data behind them.[23] SNP comparisons of samples sold under one name are covered under genetic diversity.
From one panel to a landrace
A marker-trait association is measured in the plants tested. It carries over only where marker and gene remain linked and the gene still segregates: a mapped locus may be irrelevant in another population where it does not segregate.[53] Across plant breeding thousands of associations have been reported and far fewer put to use, with effect estimates for complex traits often inconsistent.[54]
In a panel of 145 Iranian landrace accessions the main loci for cannabinoid traits lay on chromosomes 5, 3 and 1. These loci are polymorphic in landraces and fixed in modern cultivars. The region holding the synthase genes gave only minor signals.[45] A marker at such a locus would be silent in those cultivars. The sex and chemotype assays above were tested on the hemp, clinical, feral and commercial material named in each study, and a result from those sets is evidence about those sets.
Lynch and colleagues cautioned that strains offered as "landrace genetics" by producers and seed sellers may or may not be free of admixture, which can be a problem for two widely used clustering programs.[43] A group recovered by markers is a group among the plants sampled. It does not by itself establish a landrace, a species or the identity of a population that was not typed.
See also
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 Lübberstedt, T.; Bhattacharyya, M.; Suza, W. (2023). "Markers and Sequencing". In Suza, W.; Lamkey, K. (eds.). Molecular Plant Breeding. Iowa State University Digital Press. doi:10.31274/isudp.2023.133.
- ↑ 2.0 2.1 Mandolino, G.; Carboni, A. (2004). "Potential of marker-assisted selection in hemp genetic improvement". Euphytica. 140 (1–2): 107–120. doi:10.1007/s10681-004-4759-6.
- ↑ Ouborg, N.J.; Pertoldi, C.; Loeschcke, V.; Bijlsma, R.(.; Hedrick, P.W. (2010). "Conservation genetics in transition to conservation genomics". Trends in Genetics. 26 (4): 177–187. doi:10.1016/j.tig.2010.01.001.
- ↑ 4.0 4.1 4.2 Welling, M.T.; Shapter, T.; Rose, T.J.; Liu, L.; Stanger, R.; King, G.J. (2016). "A belated green revolution for Cannabis: virtual genetic resources to fast-track cultivar development". Frontiers in Plant Science. 7 1113. doi:10.3389/fpls.2016.01113.
- ↑ de Meijer, E.P.M.; Keizer, L.C.P. (1996). "Patterns of diversity in Cannabis". Genetic Resources and Crop Evolution. 43 (1): 41–52. doi:10.1007/bf00126939.
- ↑ 6.0 6.1 6.2 Somody, G.; Molnár, Z. (2025). "Flowering synchronization using artificial light control for crossbreeding hemp (Cannabis sativa L.) with varied flowering times". Plants. 14 (4) 594. doi:10.3390/plants14040594.
- ↑ 7.0 7.1 Davinack, D. (2024). Molecular Ecology & Evolution: An Introduction. Norton, Massachusetts: Wheaton College. pp. 153–154.
- ↑ 8.0 8.1 8.2 Hillig, K.W. (2005). "Genetic evidence for speciation in Cannabis (Cannabaceae)". Genetic Resources and Crop Evolution. 52 (2): 161–180. doi:10.1007/s10722-003-4452-y.
- ↑ Williams, J.G.K.; Kubelik, A.R.; Livak, K.J.; Rafalski, J.A.; Tingey, S.V. (1990). "DNA polymorphisms amplified by arbitrary primers are useful as genetic markers". Nucleic Acids Research. 18 (22): 6531–6535. doi:10.1093/nar/18.22.6531.
- ↑ 10.0 10.1 10.2 Nybom, H. (2004). "Comparison of different nuclear DNA markers for estimating intraspecific genetic diversity in plants". Molecular Ecology. 13 (5): 1143–1155. doi:10.1111/j.1365-294x.2004.02141.x.
- ↑ 11.0 11.1 11.2 Mandolino, G.; Carboni, A.; Forapani, S.; Faeti, V.; Ranalli, P. (1999). "Identification of DNA markers linked to the male sex in dioecious hemp (Cannabis sativa L.)". Theoretical and Applied Genetics. 98 (1): 86–92. doi:10.1007/s001220051043.
- ↑ Jones, C.J.; Edwards, K.J.; Castaglione, S.; Winfield, M.O.; Sala, F.; van de Wiel, C.; et al. (1997). "Reproducibility testing of RAPD, AFLP and SSR markers in plants by a network of European laboratories". Molecular Breeding. 3 (5): 381–390. doi:10.1023/a:1009612517139.
- ↑ 13.0 13.1 Vos, P.; Hogers, R.; Bleeker, M.; Reijans, M.; Lee, T.V.D.; Hornes, M.; et al. (1995). "AFLP: a new technique for DNA fingerprinting". Nucleic Acids Research. 23 (21): 4407–4414. doi:10.1093/nar/23.21.4407.
- ↑ 14.0 14.1 Mueller, U.G.; Wolfenbarger, L.L. (1999). "AFLP genotyping and fingerprinting". Trends in Ecology & Evolution. 14 (10): 389–394. doi:10.1016/s0169-5347(99)01659-6.
- ↑ Tautz, D. (1989). "Hypervariability of simple sequences as a general source for polymorphic DNA markers". Nucleic Acids Research. 17 (16): 6463–6471. doi:10.1093/nar/17.16.6463.
- ↑ 16.0 16.1 Putman, A.I.; Carbone, I. (2014). "Challenges in analysis and interpretation of microsatellite data for population genetic studies". Ecology and Evolution. 4 (22): 4399–4428. doi:10.1002/ece3.1305.
- ↑ Elshire, R.J.; Glaubitz, J.C.; Sun, Q.; Poland, J.A.; Kawamoto, K.; Buckler, E.S.; Mitchell, S.E. (2011). "A robust, simple genotyping-by-sequencing (GBS) approach for high diversity species". PLoS ONE. 6 (5) e19379. doi:10.1371/journal.pone.0019379.
- ↑ 18.0 18.1 Lachance, J.; Tishkoff, S.A. (2013). "SNP ascertainment bias in population genetic analyses: why it is important, and how to correct it". BioEssays. 35 (9): 780–786. doi:10.1002/bies.201300014.
- ↑ 19.0 19.1 Zhang, Q.; Chen, X.; Guo, H.; Trindade, L.M.; Salentijn, E.M.J.; Guo, R.; Guo, M.; Xu, Y.; Yang, M. (2018). "Latitudinal adaptation and genetic insights into the origins of Cannabis sativa L." Frontiers in Plant Science. 9 1876. doi:10.3389/fpls.2018.01876.
- ↑ 20.0 20.1 Gilmore, S.; Peakall, R.; Robertson, J. (2007). "Organelle DNA haplotypes reflect crop-use characteristics and geographic origins of Cannabis sativa". Forensic Science International. 172 (2–3): 179–190. doi:10.1016/j.forsciint.2006.10.025.
- ↑ Väli, Ü.; Einarsson, A.; Waits, L.; Ellegren, H. (2008). "To what extent do microsatellite markers reflect genome-wide genetic diversity in natural populations?". Molecular Ecology. 17 (17): 3808–3817. doi:10.1111/j.1365-294x.2008.03876.x.
- ↑ 22.0 22.1 22.2 22.3 Dufresnes, C.; Jan, C.; Bienert, F.; Goudet, J.; Fumagalli, L. (2017). "Broad-scale genetic diversity of Cannabis for forensic applications". PLoS ONE. 12 (1) e0170522. doi:10.1371/journal.pone.0170522.
- ↑ 23.0 23.1 Cull, A.; Joly, D.L. (2025). "Development and validation of a minimal SNP genotyping panel for the differentiation of Cannabis sativa cultivars". BMC Genomics. 26 (1) 83. doi:10.1186/s12864-025-11263-z.
- ↑ 24.0 24.1 Sawler, Jason; Stout, Jake M.; Gardner, Kyle M.; Hudson, Darryl; Vidmar, John; Butler, Laura; Page, Jonathan E.; Myles, Sean (2015). "The genetic structure of marijuana and hemp". PLOS ONE. 10 (8) e0133292. doi:10.1371/journal.pone.0133292.
- ↑ 25.0 25.1 Soorni, A.; Fatahi, R.; Haak, D.C.; Salami, S.A.; Bombarely, A. (2017). "Assessment of genetic diversity and population structure in Iranian Cannabis germplasm". Scientific Reports. 7 (1) 15668. doi:10.1038/s41598-017-15816-5.
- ↑ Manansala-Siazon, S.E.; Siazon, P.M.; Tandayu, E.; Garcia-de Heer, L.; Burn, A.; et al. (2025). "Seed the difference: QTL mapping reveals several major loci for seed size in Cannabis sativa L." Plants. 14 (24) 3853. doi:10.3390/plants14243853. PMC 12737016.
- ↑ 27.0 27.1 27.2 27.3 27.4 Riera-Begué, A.; Toscani, M.; Malik, A.; Dowling, C.A.; Schilling, S.; Melzer, R. (2025). "A simple and reliable PCR-based method to differentiate between XX and XY sex genotypes in Cannabis sativa". Planta. 262 (4) 87. doi:10.1007/s00425-025-04804-z.
- ↑ Sakamoto, K.; Shimomura, K.; Komeda, Y.; Kamada, H.; Satoh, S. (1995). "A male-associated DNA sequence in a dioecious plant, Cannabis sativa L.". Plant and Cell Physiology. 36 (8): 1549–1554. doi:10.1093/oxfordjournals.pcp.a078920.
- ↑ Törjék, O.; Bucherna, N.; Kiss, E.; Homoki, H.; Finta-Korpelová, Z.; Bócsa, I.; Nagy, I.; Heszky, L.E. (2002). "Novel male-specific molecular markers (MADC5, MADC6) in hemp". Euphytica. 127 (2): 209–218. doi:10.1023/A:1020204729122.
- ↑ Techen, N.; Chandra, S.; Lata, H.; ElSohly, M.; Khan, I. (2010). "Genetic identification of female Cannabis sativa plants at early developmental stage". Planta Medica. 76 (16): 1938–1939. doi:10.1055/s-0030-1249978.
- ↑ Sakamoto, K.; Abe, T.; Matsuyama, T.; Yoshida, S.; Ohmido, N.; Fukui, K.; Satoh, S. (2005). "RAPD markers encoding retrotransposable elements are linked to the male sex in Cannabis sativa L.". Genome. 48 (5): 931–936. doi:10.1139/g05-056.
- ↑ 32.0 32.1 Prentout, D.; El Aoudati, S.; Mathis, F.; Marais, G.A.B.; Henri, H. (2025). "Promising high fidelity genetic markers for sexing Cannabis sativa seedlings". G3: Genes, Genomes, Genetics. 15 (6) jkaf077. doi:10.1093/g3journal/jkaf077.
- ↑ 33.0 33.1 33.2 33.3 Toth, J.A.; Stack, G.M.; Cala, A.R.; Carlson, C.H.; Wilk, R.L.; Crawford, J.L.; et al. (2020). "Development and validation of genetic markers for sex and cannabinoid chemotype in Cannabis sativa L." GCB Bioenergy. 12 (3): 213–222. doi:10.1111/gcbb.12667.
- ↑ de Meijer, E.P.M.; Bagatta, M.; Carboni, A.; Crucitti, P.; Moliterni, V.M.C.; Ranalli, P.; Mandolino, G. (2003). "The inheritance of chemical phenotype in Cannabis sativa L.". Genetics. 163 (1): 335–346. doi:10.1093/genetics/163.1.335.
- ↑ Kojoma, M.; Seki, H.; Yoshida, S.; Muranaka, T. (2006). "DNA polymorphisms in the tetrahydrocannabinolic acid (THCA) synthase gene in "drug-type" and "fiber-type" Cannabis sativa L.". Forensic Science International. 159 (2–3): 132–140. doi:10.1016/j.forsciint.2005.07.005.
- ↑ Staginnus, C.; Zörntlein, S.; de Meijer, E. (2014). "A PCR marker linked to a THCA synthase polymorphism is a reliable tool to discriminate potentially THC-rich plants of Cannabis sativa L.". Journal of Forensic Sciences. 59 (4): 919–926. doi:10.1111/1556-4029.12448.
- ↑ 37.0 37.1 Wenger, J.P.; Dabney, C.J.; ElSohly, M.A.; Chandra, S.; Radwan, M.M.; Majumdar, C.G.; Weiblen, G.D. (2020). "Validating a predictive model of cannabinoid inheritance with feral, clinical, and industrial Cannabis sativa". American Journal of Botany. 107 (10): 1423–1432. doi:10.1002/ajb2.1550. PMC 7702092.
- ↑ Allen, K.; Torres, A.; Gaudino, R. (2026). "The structure of the chemotype determining locus in Cannabis sativa". Plant Direct. 10 (5) e70166. doi:10.1002/pld3.70166.
- ↑ Faeti, V.; Mandolino, G.; Ranalli, P. (1996). "Genetic diversity of Cannabis sativa germplasm based on RAPD markers". Plant Breeding. 115 (5): 367–370. doi:10.1111/j.1439-0523.1996.tb00935.x.
- ↑ Forapani, S.; Carboni, A.; Paoletti, C.; Moliterni, V.M.C.; Ranalli, P.; Mandolino, G. (2001). "Comparison of hemp varieties using random amplified polymorphic DNA markers". Crop Science. 41 (6): 1682–1689. doi:10.2135/cropsci2001.1682.
- ↑ 41.0 41.1 41.2 Gilmore, S.; Peakall, R.; Robertson, J. (2003). "Short tandem repeat (STR) DNA markers are hypervariable and informative in Cannabis sativa: implications for forensic investigations". Forensic Science International. 131 (1): 65–74. doi:10.1016/s0379-0738(02)00397-3.
- ↑ Datwyler, S.L.; Weiblen, G.D. (2006). "Genetic variation in hemp and marijuana (Cannabis sativa L.) according to amplified fragment length polymorphisms". Journal of Forensic Sciences. 51 (2): 371–375. doi:10.1111/j.1556-4029.2006.00061.x.
- ↑ 43.0 43.1 Lynch, R.C.; Vergara, D.; Tittes, S.; White, K.; Schwartz, C.J.; Gibbs, M.J.; et al. (2016). "Genomic and chemical diversity in Cannabis". Critical Reviews in Plant Sciences. 35 (5–6): 349–363. doi:10.1080/07352689.2016.1265363.
- ↑ 44.0 44.1 Henry, P.; Khatodia, S.; Kapoor, K.; Gonzales, B.; Middleton, A.; Hong, K.; et al. (2020). "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 of Cannabis Research. 2 (1) 26. doi:10.1186/s42238-020-00036-y.
- ↑ 45.0 45.1 Babaei, M.; Torkamaneh, D. (2026). "Genetic architecture of phenological, morphological, and phytochemical traits in Cannabis landraces". The Plant Genome. 19 (2) e70243. doi:10.1002/tpg2.70243.
- ↑ Gillan, R.; Cole, M.D.; Linacre, A.; Thorpe, J.W.; Watson, N.D. (1995). "Comparison of Cannabis sativa by random amplification of polymorphic DNA (RAPD) and HPLC of cannabinoids: a preliminary study". Science & Justice. 35 (3): 169–177. doi:10.1016/s1355-0306(95)72658-2.
- ↑ Alghanim, H.J.; Almirall, J.R. (2003). "Development of microsatellite markers in Cannabis sativa for DNA typing and genetic relatedness analyses". Analytical and Bioanalytical Chemistry. 376 (8): 1225–1233. doi:10.1007/s00216-003-1984-0.
- ↑ Howard, C.; Gilmore, S.; Robertson, J.; Peakall, R. (2008). "Developmental validation of a Cannabis sativa STR multiplex system for forensic analysis". Journal of Forensic Sciences. 53 (5): 1061–1067. doi:10.1111/j.1556-4029.2008.00792.x.
- ↑ Mendoza, M.A.; Mills, D.K.; Lata, H.; Chandra, S.; ElSohly, M.A.; Almirall, J.R. (2009). "Genetic individualization of Cannabis sativa by a short tandem repeat multiplex system". Analytical and Bioanalytical Chemistry. 393 (2): 719–726. doi:10.1007/s00216-008-2500-3.
- ↑ Köhnemann, S.; Nedele, J.; Schwotzer, D.; Morzfeld, J.; Pfeiffer, H. (2012). "The validation of a 15 STR multiplex PCR for Cannabis species". International Journal of Legal Medicine. 126 (4): 601–606. doi:10.1007/s00414-012-0706-6.
- ↑ Schwabe, Anna L.; McGlaughlin, Mitchell E. (2019). "Genetic tools weed out misconceptions of strain reliability in Cannabis sativa: implications for a budding industry". Journal of Cannabis Research. 1 (1) 3. doi:10.1186/s42238-019-0001-1.
- ↑ Soler, S.; Gramazio, P.; Figàs, M.R.; Vilanova, S.; Rosa, E.; Llosa, E.R.; et al. (2017). "Genetic structure of Cannabis sativa var. indica cultivars based on genomic SSR (gSSR) markers: implications for breeding and germplasm management". Industrial Crops and Products. 104: 171–178. doi:10.1016/j.indcrop.2017.04.043.
- ↑ Lübberstedt, T.; Beavis, W.; Suza, W. (2023). "Marker Assisted Selection and Genomic Selection". In Suza, W.; Lamkey, K. (eds.). Molecular Plant Breeding. Iowa State University Digital Press. doi:10.31274/isudp.2023.133.
- ↑ Bernardo, R. (2008). "Molecular markers and selection for complex traits in plants: learning from the last 20 years". Crop Science. 48 (5): 1649–1664. doi:10.2135/cropsci2008.03.0131.