Classification of cannabis strains in the Canadian market with discriminant analysis of principal components using genome-wide single nucleotide polymorphisms

An analysis of the cultivation, consumption and composition of home-grown cannabis following decriminalisation in the Australian Capital Territory

The Australian Capital Territory (ACT), a region that includes Australia's capital, Canberra, decriminalised small-scale cannabis cultivation and possession in January 2020. Here, we examined cannabis use and cultivation behaviours, experiences and attitudes of current and past small-scale ACT cannabis cultivators. ACT residents (n = 311) who currently cultivate or have previously cultivated cannabis completed a cross-sectional online survey ('CAN-ACT') and provided home-grown cannabis for phytocannabinoid analysis (optional). Reasons for cultivation included a preference for home-grown cannabis to self-supply, enjoyment of the process and avoiding criminal networks. Cannabis intake was a median of 1 gram on a typical day used and the number of plants grown per year was a median of 4. Various cultivation challenges were identified, most commonly mould, nutrient deficiency and spider mites. Cannabis samples (n = 71) generally exhibited moderate THC content (mean 8.99 ± SEM 0.51% [w/w]) and low CBD content (< 0.1%). Few samples exceeded contaminant guidelines for heavy metals or pesticides. Respondents identified various grey areas in current legislation that might lead to inadvertent criminal activity, and many (52%) remained anxious about arrest. In general, recent legislative changes appear to support community needs. Options for further legislative refinement are discussed.

Development and validation of a minimal SNP genotyping panel for the differentiation of Cannabis sativa cultivars

BACKGROUND

Due to its previously illicit nature, Cannabis sativa had not fully reaped the benefits of recent innovations in genomics and plant sciences. However, Canada's legalization of C. sativa and products derived from its flower in 2018 triggered significant new demand for robust genotyping tools to assist breeders in meeting consumer demands. Early molecular marker-based research on C. sativa focused on screening for plant sex and chemotype, and more recent research has sought to use molecular markers to target traits of agronomic interest, to study populations and to differentiate between C. sativa cultivars.

RESULTS

In this study, we have conducted whole genome sequencing of 32 cultivars, mined the sequencing data for SNPs, developed a reduced SNP genotyping panel to discriminate between sequenced cultivars, then validated the 20-SNP panel using DNA from the sequenced cultivars and tested the assays on commercially available dried flower. The assay conversion rate was higher in DNA extracted from fresh plant material than in DNA extracted from dried flower samples. However, called genotypes were internally consistent, highlighting discrepancies between genotypes detected using sequencing data and observed using genotyping assays. The primary contributions of this work are to clearly document the process used to develop minimal SNP genotyping panels, the feasibility of using such panels to differentiate between C. sativa cultivars, and outline improvements and goals for future iterations of PCR-based, minimal SNP panels to enable efficient development genotyping tools to identify and screen C. sativa cultivars.

CONCLUSIONS

Our key recommendations are to increase sampling density to account for intra-cultivar variability; leverage higher read length paired-end short-read technology; conduct in-depth pre- and post-processing of reads, mapping, and variant calling data; integrate trait-associated loci to develop multi-purpose panels; and use iterative approaches for in vitro validation to ensure that only the most discriminant and performant SNPs are retained.

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

The iconic, palmately compound leaves of Cannabis have attracted significant attention in the past. However, investigations into the genetic basis of leaf shape or its connections to phytochemical composition have yielded inconclusive results. This is partly due to prominent changes in leaflet number within a single plant during development, which has so far prevented the proper use of common morphometric techniques. Here, we present a new method that overcomes the challenge of nonhomologous landmarks in palmate, pinnate, and lobed leaves, using Cannabis as an example. We model corresponding pseudo-landmarks for each leaflet as angle-radius coordinates and model them as a function of leaflet to create continuous polynomial models, bypassing the problems associated with variable number of leaflets between leaves. We analyze 341 leaves from 24 individuals from nine Cannabis accessions. Using 3591 pseudo-landmarks in modeled leaves, we accurately predict accession identity, leaflet number, and relative node number. Intra-leaf modeling offers a rapid, cost-effective means of identifying Cannabis accessions, making it a valuable tool for future taxonomic studies, cultivar recognition, and possibly chemical content analysis and sex identification, in addition to permitting the morphometric analysis of leaves in any species with variable numbers of leaflets or lobes.

A forensic application of genetic markers for distinction between drug-type and fiber-type Cannabis sativa L

Genetic markers can represent a valuable tool for forensic purposes in discriminating between fiber-type and drug-type cannabis. The aim of this research was to evaluate developed genetic markers for tetrahydrocannabinolic acid synthase (THCAS) when applied on certified hemp (14 varieties) and forensic casework samples of four chemotypes (40 seizures). Chemotype-associated PCR-based markers did not enable reliable selective amplification despite the difference in cannabinoid composition. In order to characterize forensic samples of unknown origin, THCAS sequencing was performed. The comparison of THCAS sequences, including additional accessions, indicated high genetic similarity of hemp varieties. Confiscated samples of intermediate, THC, CBD and CBG type were clearly separated from fiber-type accessions and assigned to drug-type cluster. Despite the unknown origin, their position on the tree support the notion that they are more related to drug-type accessions than to the fiber-type. However, no clear distinction between chemotypes was found. Furthermore, 26 amino acid substitutions were revealed in THCAS that clearly separate hemp varieties and neither of them cluster with any other tested sample.

On offer to Ontario consumers three years after legalization: A profile of cannabis products, cannabinoid content, plant type, and prices

INTRODUCTION

Cannabis was legalized in Canada in October 2018, regulating the production, distribution, sale, and possession of dried cannabis and cannabis oils. Additional products were legalized 1 year later, including edibles, concentrates, and topicals, with new lines of commercial products coming to market. Ontario is the most populous province in Canada and has the largest cannabis market with the highest number of in-person retail stores and the most cannabis products available online. This study aims to create a profile of products available to consumers three years after legalization by summarizing types of products, THC and CBD potency, plant type, and prices of product sub-categories.

METHODS

We extracted data from the website of the Ontario Cannabis Store (OCS)-the public agency overseeing the only online store and sole wholesaler to all authorized in-person stores-in the first quarter of 2022 (January 19-March 23). We used descriptive analyses to summarize the data. A total of 1,771 available products were mapped by route of administration into inhalation (smoking, vaping, and concentrates), ingestible (edibles, beverages, oils, and capsules) and topical.

RESULTS

Most inhalation products included ≥20%/g THC (dried flower: 94%; cartridges: 96%; resin: 100%) while ingestible products had similar proportions of THC and CBD content. Indica-dominant products tend to be more prominent in inhalation products while sativa-dominant products tend to be more prominent in ingestible products. The average sale price of cannabis was 9.30 $/g for dried flower, 5.79 $/0.1g for cartridges, 54.82 $/g for resin, 3.21 $/unit for soft chews, 1.37 $/ml for drops, 1.52 $/unit for capsules, and 39.94 $/product for topicals.

DISCUSSION

In summary, a wide variety of cannabis products were available to Ontarians for different routes of administration and provides numerous indica-dominant, sativa-dominant, and hybrid/blend options. The current market for inhalation products however is geared towards the commercialization of high-THC products.

Genetic Variants Associated with Long-Terminal Repeats Can Diagnostically Classify Cannabis Varieties

Cannabis sativa (Cannabis) has recently been legalized in multiple countries globally for either its recreational or medicinal use. This, in turn, has led to a marked increase in the number of Cannabis varieties available for use in either market. However, little information currently exists on the genetic distinction between adopted varieties. Such fundamental knowledge is of considerable value and underpins the accelerated development of both a nascent pharmaceutical industry and the commercial recreational market. Therefore, in this study, we sought to assess genetic diversity across 10 Cannabis varieties by undertaking a reduced representation shotgun sequencing approach on 83 individual plants to identify variations which could be used to resolve the genetic structure of the assessed population. Such an approach also allowed for the identification of the genetic features putatively associated with the production of secondary metabolites in Cannabis. Initial analysis identified 3608 variants across the assessed population with phylogenetic analysis of this data subsequently enabling the confident grouping of each variety into distinct subpopulations. Within our dataset, the most diagnostically informative single nucleotide polymorphisms (SNPs) were determined to be associated with the long-terminal repeat (LTRs) class of retroelements, with 172 such SNPs used to fully resolve the genetic structure of the assessed population. These 172 SNPs could be used to design a targeted resequencing panel, which we propose could be used to rapidly screen different Cannabis plants to determine genetic relationships, as well as to provide a more robust, scientific classification of Cannabis varieties as the field moves into the pharmaceutical sphere.

Potential of Impedance Flow Cytometry to Assess the Viability and Quantity of Cannabis sativa L. Pollen

Over the last decade, efforts to breed new Cannabis sativa L. cultivars with high Cannabidiol (CBD) and other non-psychoactive cannabinoids with low tetrahydrocannabinol (THC) levels have increased. In this context, the identification of the viability and quantity of pollen, which represents the fitness of male gametophytes, to accomplish successful pollination is of high importance. The present study aims to evaluate the potential of impedance flow cytometry (IFC) for the assessment of pollen viability (PV) and total number of pollen cells (TPC) in two phytocannabinoid-rich cannabis genotypes, KANADA (KAN) and A4 treated with two different chemical solutions, silver thiosulfate solution (STS) and gibberellic acid (GA3). Pollen was collected over a period of 8 to 24 days after flowering (DAF) in a greenhouse experiment. Impedance flow cytometry (IFC) technology was used with Cannabis sativa to assess the viability and quantity of pollen. The results showed that the number of flowers per plant was highest at 24 DAF for both genotypes, A4 (317.78) and KAN (189.74). TPC induced by STS was significantly higher compared to GA3 over the collection period of 8 to 24 DAF with the highest mean TPC of 1.54 × 105 at 14 DAF. STS showed significantly higher viability of pollen compared to GA3 in genotype KAN, with the highest PV of 78.18% 11 DAF. Genotype A4 also showed significantly higher PV with STS at 8 (45.66%), 14 (77.88%), 18 (79.37%), and 24 (51.92%) DAF compared to GA3. Furthermore, counting the numbers of flowers did not provide insights into the quality and quantity of pollen; the results showed that PV was highest at 18 DAF with A4; however, the number of flowers per plant was 150.33 at 18 DAF and was thus not the maximum of produced flowers within the experiment. IFC technology successfully estimated the TPC and differentiated between viable and non-viable cells over a period of 8 to 24 DAF in tested genotypes of Cannabis sativa. IFC seems to be an efficient and reliable method to estimate PV, opening new chances for plant breeding and plant production processes in cannabis.