Polygenetic Inheritance

Polygenetic inheritance describes traits controlled by multiple genes, where each gene contributes small additive effects to the final phenotype. In cannabis breeding, most horticultural characteristics—plant height, flowering time, leaf morphology, and terpene profiles—are polygenetic traits rather than single-gene markers. This polygenic architecture means breeders observe continuous variation across populations rather than discrete categories, making selection gradual and often requiring multiple generations to stabilize desired traits. Understanding polygenetic inheritance is foundational to modern cannabis genetics, as it explains why offspring from the same parents can display wide phenotypic ranges and why consistent breeding lines require careful stabilization work.

Breeders working with polygenetic traits employ selection strategies like line stabilization and backcrossing to concentrate favorable alleles across multiple loci. Genomic marker-assisted selection increasingly helps identify and track favorable allele combinations that might otherwise require years of phenotypic observation.