Cannabis Genetics

How Modern Genetics Influences Cannabis Strains

Some 150 years ago, an Austrian fellow by the name of Gregor Mendel revolutionized our understanding of the inheritance of the traits that define us. With naught but a green thumb and the observation of several generations of pea plants and their characteristics, Mendel theorized nature’s method for how these organisms inherited their shape and color. The most notable results of his research were three laws that are commonly incorporated in the manipulation of the genotypic and phenotypic expressions of the desired traits in a wide variety of lifeforms. Quite famously, cannabis has been crossbred for years according to these principles.

Firstly, Mendel established that each gene exists as a pair in adult cells that are randomly separated and sorted into the different sex cells produced by a particular specimen to be inherited individually from the parent. This random assortment accounts for genetic variance in nature that often give rise to unique phenotypes that can prove more desirable at survival or for an industrial application.

The Story of Sativa and Indica

In cannabis, a notable example of this is the rise of the most distinct phenotypic classification; Sativa and Indica. The different physical characteristics expressed in these two variants of the same species of plant more than likely arose from their attributes being more favorable to the location in which they originated.

The wider leaves of the Indica or the taller growing Sativa only appear in those forms because the absence of those traits in their cousins meant they weren’t able to compete for sunlight or were too easily accessible to foraging animals over hundreds of years. This concept is known as the Law of Segregation.

Second, pea plant experiments uncovered that different genotypes are sorted separately as they are distributed to the gametes, or sex cells. The implication of this finding was that a gene defining how tall a pea plant was had no bearing on its color, and that those traits were not related in how they were passed on to the progeny. In understanding this, Mendel could then isolate plants expressing particular phenotypes in order to study what patterns the traits of inheritance would follow as the next generations were fertilized alongside other plants sharing the same phenotypes. A generation later, it was noted that the frequency of those shared characteristics increased dramatically and predictably.

The expert use of this principle has been applied in the cannabis industry to cross different phenotypes for the purpose of creating strains that exhibit the highest concentrations of particular cannabinoids (THC, CBD, etc.) and is known as the Law of Independent Assortment.

Lastly, of all the traits expressed during Mendel’s experiments, many proved quite stubborn and showed no variance down through several generations. Some plants remained a white color throughout several cycles of genetic redistribution but varied in their height and form. What he began to believe was a hole in his theories actually proved to be a prime example of the Law of Dominance. In the world of genetics, not all traits are created equal. Within the genetic pair that defines a trait, some individual genes take precedence in their expression over others and will quickly overtake a gene pool. When gauging the quality of a particular plants’ genetics, cannabis or otherwise, a term often used is “rusticity. This adjective defines how resistant a particular pedigree is to being influenced by the introduction of novel gene set.

Cannabis applications aside, genetics are the operating system for life and hold an infinite number of applications. Mendel’s applications might have been elementary, but it more than earned him the title of the father of modern genetics.

Share on facebook
Share on google
Share on twitter
Share on linkedin