Marajuana DNA Effect MyHappyGenes

Understanding the Genetic Roots of Marijuana Use

Research on marijuana use disorders has greatly expanded as more states legalize marijuana use. This includes studies that help uncover the connections between genetic roots and marijuana use disorders. An international team of researchers and scientists at Washington University School of Medicine in St. Louis found two regions in our DNA that are believed to be connected to marijuana use. 

A large study exploring the possible genetic roots of cannabis use disorder has identified two regions in our DNA related to marijuana use. One of the regions has been newly identified and the other region that replicates is from a past finding. Both of these regions contribute to one’s susceptibility of becoming dependent on marijuana. 

The findings from this study were published on October 20th in Lancet Psychiatry. These findings come from the research of the international team of scientists at Washington University School of Medicine in St. Louis.

DNA and other data from nearly 21,000 people who had been diagnosed with cannabis use disorder and an additional 360,000 who did not have that diagnosis was analyzed by researchers during this study. Researchers found that there was a clear connection with cannabis use disorder and a region of DNA near the FOXP2 gene on chromosome 7. This gene has been previously linked to language development as well as risk-taking behavior. 

The study also found that a region on chromosome 8 was also involved in one’s likelihood to surfer from cannabis use disorder. The CHRNA2 gene in this region was linked to cannabis use disorder in previous studies. The CHRNA2 gene has also been linked to nicotine addiction.

Arpana Agrawal, PhD, a senior investigator and professor of psychiatry, stated, “It has been estimated that up to 20% of those who use cannabis will develop problems. When we think about why some people who use cannabis develop problems with it, about 50% of that risk is due to genetics. We identified two variants – there are likely to be many, many more genes. While the variants that we found are not currently useful in letting someone know about their personal risk, the genetic pathways might lead to better treatments for cannabis addiction in the future.”

Researchers utilized data from the Adolescent Brain Cognitive Development (ABCD) Study and found that children with higher genetic susceptibility for serious addiction to marijuana averaged a slightly lower volume of white matter in their brains. This was evident even before ever using marijuana. This evidence suggests that certain individuals are more vulnerable and susceptible to cannabis use disorder before they ever try marijuana.

Researchers also found several behavioral factors to be linked to issues with marijuana through their genetic connections. Examples of this include schizophrenia, risk-taking behavior, and lower levels of educational attainment.

While it is impossible for a person to officially develop cannabis use disorder without ever using marijuana, genetic roots may be connected to marijuana use disorder. Data from these studies suggest that genetic factors that may cause some people to begin using marijuana differ from the genes that are believed to be related to abuse issues with the drug.

Author Emma C. Johnson, PhD, a postdoctoral research associate in psychiatry, stated, “The relationship between education, marijuana use, and problems with marijuana is particularly interesting because genetic predisposition for using the drug is correlated with higher educational attainment, but genetic liability for problematic use is linked to less education. Certainly, one has to first use cannabis to develop problems, but the genetic influences on initiating use appear to be somewhat different from the genetic factors that contribute to the development of serious problems. It also is possible that those who use cannabis occasionally but don’t develop addiction may be genetically predisposed to other protective influences, such as more years of education.”

Since more that 44 states now have legalized recreational and/or medical use of cannabis, researchers believe that it is likely that more people in these states are susceptible to marijuana use disorders and other problems associated with the drug.

Dr. Agrawl explained, “As legal marijuana use rises, it’s likely some individuals will be at risk for problems. Although many consider marijuana to be less addictive than other drugs, our findings clearly confirm that people can become dependent on cannabis and that cannabis use disorder has genetic and biological underpinnings.”

Since genetic roots of marijuana use have been identified, it is more important than ever to have an in-depth knowledge of your genes. Getting your genes tested through MyHappyGenes will show you whether you have this tendency or not.  Once you are armed with this knowledge, avoidance is good, but getting your brain chemistry balanced can reduce the cravings for various addictive substances such as cannabis.