Population Genetics "Conservation of allele frequencies"

[Mate Dave]

From what I understand the Type 1 Type 2 and Type 3 plants are how their ratios of top cannabinoids represent express themselves..

Ace is spot on in my opinion with his analogy with NLD/ BLD but we have to consider that 'Resin Breeding' would allow for variations in architecture.. A short squat fast flowering Sativa might have the typical Haze type effect or that of a traditional hash plant and vice verca. Architecture and effects of cultivated vareties will not neciseraly conform to those associated with wild 'Landrace' NLD/ BLD left to naturalise.

In any paper or post I write from here on in Sativa will be termed a cultivated variety as botanically that is what it is.

So I interporate it as NLD-BLD and NLH-BLH. With admixture.

Type 1 = High THC low CBD
Type 2 = Even ratios 1-1's Preferably 20%-20%
Type 3 = Low THC High CBD

They might be listed somewhere in a paper. I'm sure it's like common knowledge

If 1-1 is under 20% what's the point?

I see it that you need more plants to get anything and it's no Medical as it won't treat any particular serious illness.

 

[PetePrice]

Here are the 3 types;

Identification of Phenotypic Characteristics in Three Chemotype Categories in the Genus Cannabis

Modern Cannabis cultivars are morphologically distinguished by their leaflet shapes (wide for “Indica” and narrow for “Sativa”) by users and breeders. However, there are no scientific bases or references for determining the shape of these leaflets. In addition, these two categories contained...

journals.ashs.org

just stiking another paper here for ref, this is for selfing and where a punnett/mendalian is useful... ( this was chimeras work)

https://www.thieme-connect.de/products/ejournals/pdf/10.1055/s-0043-122240.pdf

 

[acespicoli]

IK= Kerala
Table 1. Accession details and number of Cannabis leaves collected and analyzed in the study.

Accession ID	Accession type	Location/cultivar name	No. of individuals	No. of leaves collected	No. of leaves analyzed
AM15	Wild/feral	Armenia, Sjunik marz, Goris town	5	90	74
BNG	Wild/feral	Bangladesh, Rangpur, Carmichael College Campus	1	14	10
FUT75	Cultivar	Futura 75	2	45	30
HU1	Wild/feral	Hungary, Nyírvasvári	4	83	68
IK	Landrace	India, Kerala	4	92	53
IKL	Landrace	India, Kullu	4	69	47
MAR	Landrace	Morocco, North Morocco	1	18	15
MN9	Wild/feral	Mongolia, Selenge aimag, Baruunburen sum	1	14	10
RO1	Wild/feral	Romania, Mangalija	2	36	34

Intra‐leaf modeling of Cannabis leaflet shape produces leaf models that predict genetic and developmental identities​

DOI:10.1111/nph.19817

 

[acespicoli]

Phytochemical Characterization of Cannabis sativa L.

Chemotype V Reveals Three New Dihydrophenanthrenoids That Favorably Reprogram Lipid Mediator Biosynthesis in Macrophages - Scientific Figure on ResearchGate. Available from: https://www.researchgate.net/figure/Cannabis-sativa-L-chemotypes_tbl1_362768691 [accessed 20 Feb 2025]

Table 1.​

Cannabis sativa L. chemotypes.

Chemotype​	Major Cannabinoids​	Classification​
I​	Drug-type plants (narcotic) with high content of the psychotropic Δ9-THC​	Drug-type plant (narcotic)​
II​	Medicinal cannabis with Δ9-THC/CBD 1:1​	Fiber-type​
III​	Industrial fiber hemp with CBD as predominant and a minimum content of Δ9-THC (from 0.2% w/w to 0.6% w/w)​	Fiber-type​
IV​	Industrial fiber hemp with CBG as predominant cannabinoid​	Fiber-type​
V​	Industrial fiber hemp with almost no cannabinoids​	Fiber-type​

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The five recognized chemotypes of cannabis include:
(I) the drug-type plants (narcotic) with a high content of the psychotropic Δ9-tetrahydrocannabinol (Δ9-THC 1);
(II) medicinal cannabis with a 1:1 content of Δ9-THC 1: CBD 2;
(III) industrial fiber hemp that has CBD 2 as a predominant constituent and a minimum content of Δ9-THC 1 (0.2% w/w);
(IV) fiber-type plants that contain cannabigerol (CBG 3) as the main cannabinoid;
(V) fiber-type plants largely devoid of cannabinoids (Table 1) [4].

This is a great reference but for a population genetics thread should we deep dive the numbers more and make sure were getting the most out of this chemotype thing ?

Plants 2019, 8(11), 496; https://doi.org/10.3390/plants8110496

Figure 4. Polymorphisms of the nucleotide sequence of tetrahydrocannabinolic acid synthase (THCAS) (A) and cannabidiolic acid synthase (CBDAS) (B) causing amino acid changes in the primary structure of the protein of fiber-type and drug-type genotypes.
involving neutral (black box) and deleterious (red box) mutations of the protein sorted from PROVEAN analysis.

https://en.wikipedia.org/wiki/Lethal_allele

https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Tree&id=3483&lvl=3&keep=1&srchmode=1&unlock

 

[clockwork]

Thank you for the information you share it is greatly appreciated @acespicoli Ive been going down a rabbit hole of researching synthase genes and their inheritance lately. CBG has really caught my attention and I found this study talking about the genes involved. Not sure if you have seen or posted this one somewhere but felt it relevant to the discussion of Type IV plants:

SNP in Potentially Defunct Tetrahydrocannabinolic Acid Synthase Is a Marker for Cannabigerolic Acid Dominance in Cannabis sativa L - PMC

The regulation of cannabinoid synthesis in Cannabis sativa is of increasing research interest as restrictions around the globe loosen to allow the plant’s legal cultivation. Of the major cannabinoids, the regulation of cannabigerolic acid (CBGA) ...

pmc.ncbi.nlm.nih.gov

"In their model, de Meijer and Hammond [9] proposed that Type IV plants contained a third, null allele B0 that is biochemically unable to convert CBGA into THCA or CBDA, thus leading to CBGA accumulation. While de Meijer and Hammond [9] did not provide any sequence data to confirm their null locus model, they hypothesized that the null allele was a sequence variant or mutation of the BD allele. Onofri et al. [15] followed up with gene sequencing and found that out of the three CBGA-dominant cultivars, two contained copies of a gene with sequence homology to the CBDAS and one contained a gene with sequence homology to the THCAS. Onofri et al. [15] compared the gene sequences from their Type IV plants with “wild-type” alleles from Type I and Type III plants and concluded that the alleles in Type IV plants displayed unique single nucleotide polymorphism (SNP) patterns. Therefore, the authors proposed that these sequence variants represented null alleles and were given the names BDO, sequence variant of BD of which there were two types, and BT0, sequence variant of BT [15]."

"Plants that were genotyped as heterozygous, either containing one copy of the null THCAS allele and a CBDAS allele, or those containing one copy of the null allele and one Wt THCAS allele, showed intermediate chemotypes, in which higher amounts of CBGA were present than in their homozygous counterparts not containing a null THCAS allele. Although the average CBD:CBG ratios were not statistically significant between Type II and Type IV plants in Cross TE, the ratios are biologically meaningful and suggest that a single copy of the CBDAS present in the Type II plants is converting small amounts of CBGA to CBDA, albeit at a lower efficiency than if two copies were present. Together, the data from Crosses 1 and 2 suggest that when present only as a single copy in the genome, the CBDA and THCA synthases have a limited ability to convert CBGA, yet have additive effects when present as two copies. de Meijer and Hammond [9] noticed a similar pattern and speculated that the rate of CBG accumulation is greater than the conversion rate of the cannabinoid synthases. Although heterozygotes in both the Type I and Type III crosses had higher proportions of CBGA than the homozygotes lacking the null allele, they were, nonetheless, largely predominant in either THCA or CBDA, respectively. The presence of intermediate chemotypes, yet with obvious either THCA- or CBDA-dominance, was also reported by de Meijer and Hammond [9]. The ratio of predominant cannabinoid (THCA or CBDA) to CBGA varied among individuals and crosses (Figure 1 and Figure 2), suggesting that there are other genes involved in regulating cannabinoid production not explained or explored in the current study. Interestingly, the effect of heterozygosity (having one copy of the “null” THCAS and a single copy of a fully-functional cannabinoid synthase allele) appears to be different among the crosses. Heterozygous individuals in the FH cross appear to be more efficient in their conversion of CBGA to THCA(V) than heterozygotes in the TE are in their conversion of CBGA to CBDA (Figure 1 and Figure 2). Although noteworthy, it is perhaps not surprising as different cannabinoid synthase sequence variants have been shown to affect cannabinoid composition, including the ratios of THCA(V):CBGA(V) and CBDA:CBGA [15]. It is possible also that the putatively null sequence variant has a negative regulatory effect on the fully-functional CBDAS, but not the fully-functional THCAS. Indeed, there are likely several factors regulating cannabinoid content ratios that are not addressed in this paper and deserve further analysis. This discrepancy could also be a result of selecting the F1 for different traits; the F1 in the FH population was selected for low THCA(V) content whereas the F1 in the TE population was selected for high CBDA content (Table 3 and Table 4). These results would also suggest the presence of additional genes/loci responsible for determining cannabinoid ratios."

 

[acespicoli]

Thank you for the information you share it is greatly appreciated @acespicoli Ive been going down a rabbit hole of researching synthase genes and their inheritance lately. CBG has really caught my attention and I found this study talking about the genes involved. Not sure if you have seen or posted this one somewhere but felt it relevant to the discussion of Type IV plants:

SNP in Potentially Defunct Tetrahydrocannabinolic Acid Synthase Is a Marker for Cannabigerolic Acid Dominance in Cannabis sativa L - PMC

The regulation of cannabinoid synthesis in Cannabis sativa is of increasing research interest as restrictions around the globe loosen to allow the plant’s legal cultivation. Of the major cannabinoids, the regulation of cannabigerolic acid (CBGA) ...

pmc.ncbi.nlm.nih.gov

The cannabinoids are a interesting subject, was reading the other day about one that has 10x the power of CBD in medicinal benefits





This sequence variant of the THCAS is consistently and predictably present in the homologous state in C. sativa plants which contain CBGA as the dominant cannabinoid, as shown by crosses with both THCA(V)- and CBDA-dominant plants. Our crosses also confirm the recessive mendelian inheritance of CBGA-dominance as first reported by de Meijer and Hammond [9].


Plants that were genotyped as heterozygous, either containing one copy of the null THCAS allele and a CBDAS allele, or those containing one copy of the null allele and one Wt THCAS allele, showed intermediate chemotypes, in which higher amounts of CBGA were present than in their homozygous counterparts not containing a null THCAS allele. Although the average CBD:CBG ratios were not statistically significant between Type II and Type IV plants in Cross TE, the ratios are biologically meaningful and suggest that a single copy of the CBDAS present in the Type II plants is converting small amounts of CBGA to CBDA, albeit at a lower efficiency than if two copies were present. Together, the data from Crosses 1 and 2 suggest that when present only as a single copy in the genome, the CBDA and THCA synthases have a limited ability to convert CBGA, yet have additive effects when present as two copies. de Meijer and Hammond [9]


I have the cannabinoid book you'd enjoy reading that if you dont already have it ? PM