Cannabis is the most commonly used illegal substance throughout most of the world29; in the United States, its status straddles the ‘legal’ and ‘illegal’ categories in many states, where use was decriminalized and then legalized for medical and/or recreational use, despite continuing illegality on the federal level. This has corresponded to gradually increasing societal acceptance of cannabis use, the natural outcome of which has been increased use and childhood exposure30. In this context, working out the genetic risk for cannabis use disorder (CUD) has taken on increased importance. The first two cannabis-relevant GWAS that yielded significant results mapped risk loci for CUD in AAs in one study31 and in EUR in the other32. The next several efforts, which put together considerably larger samples via meta-analysis, did not address CUD per se, but related traits, including lifetime cannabis use33, 34 and age of first cannabis use35. The relationship these latter two traits bear to CUD is not entirely clear: these traits would appear to bear strong relationships to environmental exposures, drug availability and personality traits such as sensation seeking, as opposed
