Heritability in the narrow sense is represented by which symbol?

• A. h
• B. H^2
• C. h^2
• D. H

Answer: (C)

Heritability in the narrow sense, which quantifies the proportion of phenotypic variance in a trait that is attributable to additive genetic variance, is represented by the symbol h². This symbol specifically indicates the measurement of how much of the trait's variation is inherited, allowing researchers to predict outcomes in breeding and genetics.

The use of h² is important because it focuses on the additive effects of alleles, which can be crucial when considering traits that are influenced by multiple genes. This additive genetic variance is what drives responses to selection in breeding programs.

In contrast, H², often used to denote broad-sense heritability, includes all genetic variances, encompassing additive, dominance, and epistatic effects. The distinction between narrow-sense and broad-sense heritability is fundamental in genetics, particularly when the goal is to improve specific traits through selective breeding. The other options simply do not represent the concept of narrow-sense heritability accurately.