If broad-sense heritability for a trait is very high and narrow-sense heritability is very low, which of the following statements must be TRUE?
A) Additive variance must be high relative to total phenotypic variance.
B) Dominance variance must be high relative to total phenotypic variance.
C) Environmental variance must be high relative to total phenotypic variance.
D) Genotypic-environmental covariance must be high relative to total phenotypic variance.
E) No conclusions can be drawn without additional information.

Question

Quizplus · Accepted Answer

Broad-sense heritability includes all genetic variance (additive, dominance, and epistatic), while narrow-sense heritability includes only additive variance. If broad-sense is high and narrow-sense is low, dominance variance must be high.

If Broad-Sense Heritability for a Trait Is Very High and Narrow-Sense