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Huscher, E. L.

Publications and source records attributed to Huscher, E. L..

2 recordsLinked to original sources

Genomic evidence that governmentally produced Cannabis sativa poorly represents genetic variation available in state markets

The National Institute on Drug Abuse (NIDA) is the sole producer of Cannabis for research purposes in the United States, including medical investigation. Previous research established that cannabinoid profiles in the NIDA varieties lacked diversity and potency relative to the Cannabis produced commercially. Additionally, microsatellite marker analyses have established that the NIDA varieties are genetically divergent form varieties produced in the private legal market. Here, we analyzed the genome of multiple Cannabis varieties from diverse lineages including two produced by NIDA, and we provide further support that NIDAs varieties differ from widely available medical, recreational, or industrial Cannabis. Furthermore, our results suggest that NIDAs varieties lack diversity in the single copy portion of the genome, the maternally inherited genomes, the cannabinoid genes, and in the repetitive content of the genome. Therefore, results based on NIDAs varieties are not generalizable regarding the effects of Cannabis after consumption. For medical research to be relevant, material that is more widely used would have to be studied. Clearly, having research to date dominated by a single, non-representative source of Cannabis has hindered scientific investigation.

genomics↗

Gene copy number is associated with phytochemistry in Cannabis sativa

Gene copy number variation is known to be important in nearly every species where it has been examined. Alterations in gene copy number may provide a fast way of acquiring diversity, allowing rapid adaptation under strong selective pressures, and may also be a key component of standing genetic variation within species. Cannabis sativa plants produce a distinguishing set of secondary metabolites, the cannabinoids, many having medicinal utility. Two major cannabinoids -- THCA and CBDA -- are products of a three-step biochemical pathway. Using genomic data for 69 Cannabis cultivars from diverse lineages within the species, we found that genes encoding the synthases in this pathway vary in copy number, and that the cannabinoid paralogs may be differentially expressed. We also found that copy number partially explains variation in cannabinoid content levels among Cannabis plants.

genomics↗