Cannabis is rapidly becoming a connoisseur product. From fragrant, fruity notes of aroma to the smell of dank cheese the varieties becoming available are truly staggering. Cannabis is now bred for a variety of characteristics that include appearance, smell, taste, medical compounds and, of course, psychoactive effect. When you see a sample of cannabis of a particular color and appearance, with a unique aroma and taste what you are experiencing is the plants’ phenotype. The genetics at work to make the plant express these particular characteristics is the plants’ genotype.
Whatever you can do, or dream you can, begin it. Boldness has genius, power and magic in it.
–Johann Wolfgang von Goethe
If you understand how the genotype works you can grow the plants with the traits you want much faster and with extreme precision. Called marker-assisted selection, it’s the key to modern agriculture. In order to understand your genotype you have to map out the genetic structure, or genome of the plant. In the case of cannabis, this involves mapping out 800 million base pairs across 10 chromosomes to build the genomic map.
With the genomic map ideally, you would be able to turn up the expression of any of the hundreds of chemicals in cannabis, some that smell great, some that get you high, and some that might ease pain or might treat a disease. Decoding he cannabis genome has been tried already. In 2011, Kevin McKernan, chief scientific officer of a firm called Medicinal Genomics, made public the sequences for strains called Chemdawg and LA Confidential. And Jonathan Page, a biochemist with Canada’s National Research Council, had results for the Purple Kush genome. But these weren’t the kind of sequences anyone could use.
When geneticists decode all the base pairs of a genome it is similar to reading the punch code on a player piano roll as it unspools. However, first they have to reassemble the roll from millions of pieces. This is done by lining up the overlaps, much like putting a torn piece of paper back together. However, this method isn’t great for plants. Their genomes are naturally full of repeating sequences, which makes it almost impossible to tell which fragments overlap, they all look the same so you can’t line them up. Worse, plants tend to maintain multiple copies of their useful, core genes as backups in case something goes awry in their environment.
Cannabis breeders have made the problems even worse. They’ve been cross-breeding for a long time to pump up cannabis’s psychoactivity that modern strains can have as many as 11 copies of the gene that synthesizes THC. If the crossbred genome were a jigsaw puzzle, most of the picture would be blue sky.
These modern plants are more likely to be heterozygous, with two versions of a given gene. They yield stronger offspring. But to put together a good sequence, a reference genome, you need an exemplar that’s homozygous, with two matched sets of chromosomes.
“Make everything as simple as possible, but not simpler.”
– Albert Einstein
Getting all of this figured out is no easy task, sequencing the maize genome took 33 labs, 157 researchers, $32 million, and four years. These days, Cannabis is becoming an economic force, and more legal. Someone, somewhere, is going to do this work, to figure out how to modify cannabis with the same ease that Monsanto tweaks corn. When we think about all the medical breakthroughs being made with just a handful of cannabinoids the implications of mapping the entire cannabis genome are truly staggering. Practically any purpose cannabis is grown for can be enhanced. From smells, tastes, effects and medicinal properties, once you understand how the genes are driving the plant phenotypes you can begin to make modifications to the genes, or isolate them to produce an abundance of specific compounds from cannabinoids to terpenoids. Almost any aspect of the cannabis plant could be controlled. With Federal laws changing rapidly it may not be long before we can truly understand the remarkable potential of this amazing plant.