Media release

From: Springer Nature

Genetics of cannabis use disorder

Genetic risk factors associated with cannabis use disorder and insights into its relationships with other traits are reported in a genome-wide association study, published in Nature Genetics.

Roughly one third of individuals who use cannabis develop cannabis use disorder, defined as a problematic pattern of cannabis use leading to clinically significant impairment or distress. Negative health consequences of cannabis use disorder include declines in cognitive function and increased risk of some cancers, and societal implications include decreased productivity and accidents while intoxicated. As permissiveness around cannabis use increases, understanding the risks associated with cannabis use disorder become more necessary.

To study the genetic factors that influence the risk of developing cannabis use disorder, Joel Gelernter, Daniel Levey and colleagues performed a large-scale genome-wide association study followed by a meta-analysis using data from 1,054,365 individuals from multiple ancestry groups (886,025 European; 123,208 African; 38,289 admixed-American; and 6,843 East Asian). They then leveraged the results of these analyses to study genetic risk factors shared between cannabis use disorder and other substance use, psychiatric, and behavioral traits and to explore potential causal relationships. They observed positive genetic correlations between cannabis use disorder and several traits, including smoking initiation and alcohol dependence, in both European and African ancestry populations. They also found genetic evidence to support a potential causal influence of cannabis use disorder on lung cancer risk in the European population. They indicate that this potential relationship may have unforeseen public health consequences in the future.

The authors attempted to control for the effects of cigarette smoking in their analyses; however, they note that further work is needed to clarify the complex relationships between cannabis use, cigarette smoking and future health outcomes.