What is the transmittable gene effect?

• A. Only environmental factors that can be transmitted.
• B. Only the genetic effects that are associated with individual alleles can be predictably transmitted to the progeny (additive, BV, or EPD)
• C. All gene effects including non-additive and epistasis
• D. The effect observed in the phenotype due to management

Answer: (B)

The transmittable gene effect is the portion of genetic influence that can be passed from parents to offspring in a predictable way—the additive genetic component. Additive effects are the sum of allele effects across loci and constitute the breeding value. Because each parent reliably transmits one allele per locus, these additive effects appear in the progeny and allow us to estimate an animal’s transmitting ability, often expressed as the breeding value or estimated breeding value (EPD).

Non-additive effects, like dominance and epistasis, depend on specific allele interactions within a particular genetic background and aren’t transmitted as a simple, predictable value to all offspring, so they aren’t considered transmittable in the same sense. Environmental or management effects aren’t genetic and aren’t transmitted genetically either.