Scientists have for long wondered why the cannabinoids in hemp differ in quantity from those present in cannabis, yet these plants are genetically similar. Research was conducted to generate a chromosome map of cannabis sativa and the findings shed light on this important question.
The study brought to light the fact that the THC and CBD composition of hemp and cannabis was largely a product of mutations resulting from viruses that entered the chromosomes of the cannabis plant millions of years ago.
The result of that viral invasion at the genetic level was that cannabis split into two distinct variations, that is, hemp and cannabis. Hemp largely contains CBD while cannabis has varying amounts of CBD and THC, but cannabis has markedly higher THC levels than hemp.
The enzymes that triggered the production of the varying levels of CBD and THC in these two plants look identical at the genetic level, but they differ in genetic expression. Consequently, it is possible to extract one gene and leave the other, thereby growing a plant with only one of the major cannabinoids. For example, the THC gene can be removed so that plants with only CBD can be grown, and the same can be done to the CBD gene in cannabis.
The scientists thought that human selection was partly responsible for the wide prevalence of cannabis strains since, from ancient times, people have been known to propagate plants that gave them the desired output. Consequently, varieties that had balanced CBD and THC may have been ignored and left to disappear from the genetic pool while those with high THC were kept as our forefathers enjoyed the “high” derived from those varieties. Hemp survived this primitive form of selection because it had other uses, such as making rope from its tough fibers.
What does this research show the current crop of scientists? There is still so little known about cannabis. This information gap may not necessary be the fault of the scientific community, but it can be attributed to the decades of prohibition that made it nearly impossible to perform any meaningful research on cannabis.
Jonathan Page, one of the main researchers in this Canadian study, remarked that the legal walls are gradually collapsing, so scientists should take the lead in generating information about this versatile plant.
