Genome-wide association study (GWAS) is a useful strategy to study the genetics and ultimately the biology of hallucinations. Here we carried out the first GWAS of Ca-HL among European American (EA) (total N = 4291) and African American (AA) (total N = 3624) long-term cannabis users. We identified one genome-wide significant (GWS) signal close to the gene cholinergic receptor muscarinic 3 (CHRM3), predisposing to Ca-HL in EAs, with the finding nominally replicated in AAs.
