Why everyone should be excited about studying Cannabis.
Cannabis has many emerging medical and economical applications.
Cannabis is not only exciting politically and socially, but is also extremely interesting biologically. I didn’t mention many other cool biological aspects about the plant such as its potentials in treating a variety of diseases: medical marijuana has been used as a pain reliever, in patients with glaucoma, multiple sclerosis, Alzheimer’s disease, depression and breast cancer . Other promising uses include reducing nausea, and either increasing or decreasing appetite, depending on which varieties are used.
Hemp, which is a variety of marijuana low in second metabolite production but of high growth, can be used to extract oil and fiber. The products made out of hemp include paper, clothes, body products (lip balm, body lotion, shampoo and conditioner), food products, housing material, biodegradable plastic, isolating material and biofuel. In the future, at the Cannabis Genomic Research Initiative CGRI we hope to determine the genomic regions in Cannabis related to both the fiber and oil production in hemp and the medical benefits of resin marijuana types, creating useful collaborations between industry and basic research.
Cannabis plants exhibit amazing phenotypic diversity, especially in the production of secondary metabolites.
Cannabis plants appear to differ in numerous phenotypic aspects. For example, there is a huge diversity of secondary compounds such as terpenes, which give the plant its smell, and the cannabinoids (the plant produces at least 85 known cannabinoids, which give the plant its medicinal and psychedelic properties. In Cannabis, the production of these secondary metabolites is mostly found in the flower (buds) of the female plant. All plants produce secondary metabolites, which are usually used as chemical defenses against herbivory, pathogens, and abiotic stresses, as well as to mediate symbiotic relationships. However, in many domesticated plants, we have selected against these secondary metabolites. In Cannabis the opposite has happened, we have selected for an increase in secondary metabolites. The productions of these metabolites, both the cannabinoids and the terpenes varies between strains.
Cannabis has a long, complicated, and interesting history of domestication.
Cannabis offers that unique opportunity to study a plant that has had several events of domestication at different points in time by various cultures. The Chinese used marijuana for medical purposes and for fiber since approximately 2700 BC; the Egyptians used it medically since 1150 BC; the Indians and the Greeks and Romans used for recreation and medical purposes since 2000 BC and 200 BC respectively. Like other domesticated species such as dogs and rice, Cannabis likely has genetic signatures of domestication, in other words, regions in the genome that show signs of selection by humans.
Furthermore, Cannabis ruderalis has not been under strong selection because it lacks second metabolite production, which offers a great baseline for genome comparisons. This allows us to determine whether Cannabis genomes vary in different regions suggesting that in the multiple domestication events they were selected for different purposes. For example, we would expect that individuals that have been domesticated for fiber or oil production would have different signatures of selection than those that have been domesticated for second metabolite production.