Happiness Gene Found in THC

By: Cory Healy

Japanese scientists have discovered that a component of THC can be found within human genetics.

A polymorph of the CB1 genotype in the human cannabinoid system can greatly influence our capacity for happiness. Dr. Masahiro Matsunaga and other researchers believe this explains why some people are naturally happier than others.

To gauge how much genetics factors into happiness, scientists conducted a three-part experiment with nearly 200 volunteers. Different tests were used to measure participants’ happiness levels, based on their emotional cues from watching video clips of people being happy. Viewers ranked their moods via questionnaire and also had PET scans done of their brain activity via neuroimaging.

Those who were happier on average, it turns out, all shared the same CB1 genetic polymorph. Specifically, those with the cytosine allele CB1 polymorph had a higher subjective happiness level than their thymine-thymine counterparts. This allows for increased responses to natural cannabinoids.

As such, they are more likely to have heightened sensitivity to positive emotional events and that “positive life events may be more abundant” for them.

"The human cannabinoid receptor 1 genotypes are closely related to two aspects of happiness,” the study says. These aspects are classified as either temporary (hedonia) or as a static state (eudaimonia). While hedonia is more psychological and influenced by changes of circumstance, eudaimonia is relative to the sum of one’s life lived.

The endocannabinoid system refers to a group of lipids that bind to brain cannabinoid receptors. They're involved in several physiological processes, influencing appetite, memory, mood, and nerve stimulation.

While the study didn’t look into marijuana’s effects on subjective happiness levels, it’s important to note that the human cannabinoid receptor 1 gene encodes for eudemonia along the same pathway cannabis travels in the brain. CB1 genotypes are also found within cannabis and other plant matter, with THC regarded as the most potent among the 60+ cannabinoids that exist.

The study was published in PLOS ONE, and supported by a Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science. Dr. Matsunaga is the chief researcher at the Department of Health and Psychosocial Medicine at the Aichi Medical University School of Medicine.