Cannabis is the most widely used illicit drug in the world, and debate about the impact of its use has been fueled by policies of decriminalization and legalization. The changing legal context reiterates the importance of understanding the factors that predispose a person to use cannabis, the potential for dependence, and its associations with adverse outcomes including mental illness. The article by Sherva and colleagues1 in this issue of JAMA Psychiatry uses molecular genetics to address some of these issues by reporting the results of a genome-wide association study (GWAS) of cannabis dependence and seeking evidence for genetic overlap with 5 mental disorders.
Walters JTR, Owen MJ. Genome-wide Significant Associations for Cannabis Dependence SeverityRelevance to Psychiatric Disorders. JAMA Psychiatry. 2016;73(5):443-444. doi:10.1001/jamapsychiatry.2016.0046