How Cannabis Strain Genetics Influence the THC:CBD Ratio

How Cannabis Strain Genetics Influence the THC:CBD Ratio

June 14, 2019

Do you know what shapes your cannabis or CBD consumption experience? It’s all about the cannabinoid and terpene ratios. Learn more about CBD strain genetics and how they differ from cannabis strains with

Unlocking the Genetics of CBD Strains

When it comes to determining how a cannabis strain will affect you, it’s important to start with your THC-to-CBD ratios. The two most abundant cannabinoids in most strains are THC and CBD but they aren’t the only cannabinoids present in the cannabis plant. THC is known as the main psychoactive compound in cannabis while CBD is known for its wide range of benefits and potential medical uses. While CBD isn’t psychoactive like THC, it does have an influence on how THC affects the brain. For this reason, it’s important to look at the THC: CBD ratio of a given strain or product as this will influence the strain’s effects and determine what kind of experience you are in for.

So what decides a cannabis strain’s THC to CBD ratio? It’s genetics. Like humans, cannabis plants have a genetic code that determines the way a given plant will produce the two compounds.

How THC and CBD are Manufactured in the Cannabis Plant

THC and CBD are both derivatives of another cannabinoid called cannabigerol (CBG). Each of these compounds – CBG, CBD, and THC- are actually present in the plant as it grows, simply in an acidic form. During growth, cannabis plants are effectively making either THCA or CBDA out of CBGA (A stands for ‘acid’) but it’s only after THCA and CBDA are decarboxylated by exposure to heat or oxygen that significant levels of THC and CBD begin to appear. Essentially, that means that the heat from your CBD vape, oven, or lighter, cause a chemical chain reaction that turns the acidic forms of CBG, THC, and CBD into their more commonly known forms. For example, THCA turns into THC and CBDA turns into CBD.

It’s also important for consumers to know that THCA and CBDA don’t induce the same effects as their decarboxylated counterparts. For example, THCA isn’t psychoactive so in order to feel the effects of THC, you would have to heat the product at the right temperature, thus turning the THCA into psychoactive THC.

While CBGA can turn into THCA or CBDA (and then into CBD or THC) it cannot turn into both. Instead, the presence of an enzyme determines whether a particular strain will convert the CBGA into THCA or CBDA.

Different CBD Strain Genetics and Ratios

Like much of the plant and animal kingdom, cannabis plants inherit two copies of their genes. Put simply, the enzymes that turn CBGA into either CBDA or THCA are encoded by different versions of the same gene and because each plant gets two copies of said gene, there are only three possibilities that we currently know of:  A cannabis plant can have two copies of the gene that encodes for the transition of CBGA to THCA transition; it can have one copy each of the genes that encode for both THC and CBD transitions from CBGA, or it can have two copies of the gene that encodes for the transition of CBGA to CBD.

The three THC: CBD ratio strain categories to know about are:

  • Hemp or CBD-dominant strains where only the transition from CBGA to CBDA is possible. These strains have high levels of CBD and little to non-existent levels of THC.
  • Evenly balanced strains: When a strain receives genetics of both enzymes from its parents, it will produce both CBDA and THCA at relatively equivalent levels.
  • THC-dominant strains: Most popular in states with medical and recreational marijuana markets, these strains inherit two copies of the gene that makes only the transition from CBGA to THCA possible and have negligible levels of CBD present.

Exploring the Future of CBD Strain Genetics

While hemp strains don’t produce significant levels of THC, most commercial strains are THC-dominant category. However, with the boom of the CBD industry and the growing demand from consumers and regulators for high CBD options, high-CBD strains are rapidly growing in popularity. What high CBD strain are you curious to try?


Share Tweet