Lethal Recessives

Lethal recessive traits in cannabis are genetic conditions that typically manifest when a plant inherits two copies of a recessive allele, often resulting in non-viable or severely stunted phenotypes. These mutations are rarely encountered in commercial breeding because they either prevent seed germination, cause early seedling death, or produce plants with severe developmental abnormalities. Documentation of lethal recessives remains limited in peer-reviewed cannabis literature, though breeders working with large F2 or backcross populations occasionally report unexpected sterility, severe dwarfism, or chlorophyll deficiencies consistent with homozygous recessive expression. Understanding these traits is valuable for genetic mapping and for avoiding accidental fixation in closed breeding programs. Most lethal recessive conditions are selected against naturally during cultivation.

Breeders tracking lethal recessives typically use them as genetic markers to understand population structure and hidden heterozygosity within parent lines. Identifying these traits helps breeders predict offspring viability and avoid unintended inbreeding that might concentrate deleterious alleles.