Researchers have identified specific gene variants associated with cannabis use disorder, shedding light on the genetic risks and potential underlying mechanisms of the condition.
Cannabis use disorder is a condition characterized by problematic cannabis use, including tolerance and signs of dependence. In a groundbreaking study, scientists have identified key gene variants linked to the risk of developing this disorder. By analyzing the genomes of over 1 million individuals, the researchers discovered hotspots of genetic variation near genes related to neurons, including a dopamine receptor known to play a role in addiction. The study also revealed associations between cannabis use disorder and smoking cigarettes, substance dependence, post-traumatic stress disorder (PTSD), schizophrenia, and potentially lung cancer.
Genetic Hotspots and Neuronal Genes:
The study, published in the journal Nature Genetics, utilized data from the Million Veterans Program and other large datasets to investigate the genetic risks of cannabis use disorder. The analysis included genomes from individuals of various ancestries, with a focus on populations of European descent. The researchers identified 22 loci associated with the disorder in Europeans, two each in Africans and East Asians, and one in individuals with mixed ancestries. The hotspots of genetic variation often appeared near genes related to neurons, particularly those involved in the brain’s reward system and addiction. Surprisingly, genes related to cannabinoid receptors, which are directly affected by cannabis ingredients, did not emerge as significant factors. However, the researchers believe that larger datasets may reveal additional gene variants related to cannabinoid receptors.
Associations with Other Disorders and Behaviors:
In addition to identifying genetic loci, the researchers explored the relationship between cannabis use disorder and other disorders and behaviors. They found links between the disorder and smoking cigarettes, various forms of substance dependence, and symptoms of PTSD. Comparing these genetic patterns to those associated with general cannabis use, the researchers discovered distinct differences. While both general cannabis use and cannabis use disorder were linked to schizophrenia, the latter showed a stronger association. This finding warrants further investigation into the relationship between schizophrenia and cannabis use disorder.
Potential Link to Lung Cancer:
The study also revealed a potential genetic link between cannabis use disorder and lung cancer. Although smoking cannabis contains combustion products that could contribute to lung cancer, the researchers emphasized the need for focused studies to better understand this relationship. Notably, cannabis use disorder was also associated with cigarette smoking, a known cause of lung cancer. The researchers acknowledged the need to determine the extent to which the observed link is attributable to simultaneous cigarette smoking.
Through their comprehensive analysis of genetic data, scientists have identified gene variants associated with cannabis use disorder, shedding light on the underlying genetic risks and potential mechanisms of the condition. The study highlights the importance of expanding genomic research to include diverse populations in order to uncover more gene variants relevant to each group. The findings also emphasize the complex relationship between cannabis use disorder and other disorders and behaviors, such as smoking cigarettes, substance dependence, PTSD, schizophrenia, and potentially lung cancer. Further research is needed to fully understand these associations and their implications for prevention, treatment, and public health interventions.