The Structure of the Chemotype Determining Locus in Cannabis sativa

Abstract The chemical phenotype (chemotype) of Cannabis sativa is defined by the ratio of cannabidiolic acid (CBDA) to Δ9‐tetrahydrocannabinolic acid (THCA). Although the Mendelian segregation of these traits suggests a single‐locus biallelic system, recent sequencing and phylogenetic evidence indicate they are encoded by two distinct, tightly linked genes. The precise genomic architecture of this region, known as the B locus, has remained poorly defined. In this study, we analyzed recently released high‐quality Cannabis reference genomes to resolve the structure of