Researchers selectively bred mice for THC sensitivity, finding the trait was heritable and linked to anxiety
A selective breeding study in mice found that adolescent locomotor sensitivity to THC was moderately heritable (strongest in females from F2 to S3 generations) and that mice bred for THC sensitivity also showed increased anxiety-like behavior.
Quick Facts
What This Study Found
Researchers selectively bred mice for sensitivity or resistance to the locomotor effects of a single THC dose (10 mg/kg) during adolescence.
THC-locomotor sensitivity proved to be moderately heritable, with the strongest heritability estimates seen in females from the F2 to S3 generations.
An important correlated trait emerged: mice selected for THC-locomotor sensitivity also showed increased anxiety-like activity in the open field test, suggesting shared genetic factors between THC sensitivity and anxiety.
This is the first demonstration that adolescent THC-locomotor sensitivity can be influenced through selective breeding, establishing a genetic basis for individual differences in cannabis response.
Key Numbers
THC dose: 10 mg/kg. Selection was moderately heritable. Greatest heritability estimates in females from F2 to S3 generations. THC-sensitive lines showed significantly increased anxiety-like behavior in open field.
How They Did This
Short-term selective breeding (bidirectional selection) for adolescent locomotor response to acute THC (10 mg/kg i.p.) in the open field test. Heritability estimated across generations. Anxiety-like behavior assessed as a correlated trait.
Why This Research Matters
Individual differences in cannabis response are well-documented but poorly understood. This study establishes a genetic foundation for these differences and reveals that genetic predisposition to THC sensitivity co-occurs with anxiety-related traits, which could help explain why some individuals are more vulnerable to negative cannabis effects.
The Bigger Picture
The co-selection of THC sensitivity with anxiety traits is intriguing because anxiety is both a common reason people use cannabis and a common adverse effect. This genetic overlap could help explain the paradox of why cannabis sometimes worsens the very symptoms it is used to treat.
What This Study Doesn't Tell Us
Mouse model may not fully translate to human genetics of cannabis response. Short-term selective breeding (few generations). Only locomotor sensitivity was selected for; other aspects of THC response (reward, cognition) were not directly assessed.
Questions This Raises
- ?Do the genetic variants driving THC sensitivity in mice have human homologs?
- ?Would THC-sensitive mice also show greater vulnerability to cannabis dependence?
- ?Does the THC sensitivity-anxiety link hold across different THC doses?
Trust & Context
- Key Stat:
- Mice bred for THC sensitivity also showed increased anxiety-like behavior
- Evidence Grade:
- Preliminary. Novel selective breeding approach establishing heritability, but early-stage animal work requiring replication and extension.
- Study Age:
- Published in 2018. Genetic studies of cannabis response have continued to advance, though translating animal genetics to human populations remains challenging.
- Original Title:
- Short-Term Genetic Selection for Adolescent Locomotor Sensitivity to Delta9-Tetrahydrocannabinol (THC).
- Published In:
- Behavior genetics, 48(3), 224-235 (2018)
- Authors:
- Kasten, Chelsea R, Zhang, Yanping, Mackie, Ken(22), Boehm, Stephen L
- Database ID:
- RTHC-01714
Evidence Hierarchy
Tests effects in animals (usually mice or rats), not humans.
What do these levels mean? →Frequently Asked Questions
What does "locomotor sensitivity" to THC mean?
It refers to how much an animal's movement patterns change in response to THC. Some mice showed large changes in activity after THC (sensitive), while others showed minimal changes (resistant). This is used as a measurable proxy for overall drug sensitivity.
Why were females more heritable than males?
The study found stronger heritability estimates in females from the F2 to S3 generations, suggesting sex-specific genetic factors may influence THC sensitivity. Sex differences in cannabis response are documented in both animals and humans, possibly related to hormonal interactions with the endocannabinoid system.
Read More on RethinkTHC
- cannabis-cardiovascular-heart-risk-stroke
- cannabis-heart-cardiovascular-risk
- coughing-up-stuff-after-quitting-weed
- lung-recovery-after-quitting-smoking-weed
- lung-recovery-quitting-weed
- quitting-weed-female-hormones
- quitting-weed-weight-gain-loss-diet-appetite
- sex-after-quitting-weed
- weed-DUI-driving-impaired-cannabis-laws
- weed-acne-skin
- weed-fertility-sperm
- weed-gut-digestion-problems
- weed-heart-health
- weed-testosterone-levels
Cite This Study
https://rethinkthc.com/research/RTHC-01714APA
Kasten, Chelsea R; Zhang, Yanping; Mackie, Ken; Boehm, Stephen L. (2018). Short-Term Genetic Selection for Adolescent Locomotor Sensitivity to Delta9-Tetrahydrocannabinol (THC).. Behavior genetics, 48(3), 224-235. https://doi.org/10.1007/s10519-018-9894-2
MLA
Kasten, Chelsea R, et al. "Short-Term Genetic Selection for Adolescent Locomotor Sensitivity to Delta9-Tetrahydrocannabinol (THC).." Behavior genetics, 2018. https://doi.org/10.1007/s10519-018-9894-2
RethinkTHC
RethinkTHC Research Database. "Short-Term Genetic Selection for Adolescent Locomotor Sensit..." RTHC-01714. Retrieved from https://rethinkthc.com/research/kasten-2018-shortterm-genetic-selection-for
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.