What is the heritability if the correlation for a breeding value trait is 0.7?

What is the heritability if the correlation for a breeding value trait is 0.7?

• A. 0.7
• B. 0.49
• C. 0.25
• D. 0.84

Answer: (B)

The correct heritability value can be derived from the given correlation for a breeding value trait. Heritability is often represented in quantitative genetics as the proportion of phenotypic variance that can be attributed to genetic variance, and is calculated as the square of the correlation of breeding values between relatives.

In this scenario, if the correlation for a breeding value trait is 0.7, to find heritability, you square the correlation coefficient:

0.7 × 0.7 = 0.49.

This result indicates that 49% of the phenotype variation in that trait can be attributed to genetic factors, which provides a useful measure in breeding programs to predict the potential for progress through selection.

Understanding why the other choices do not represent the correct heritability is important for grasping the concepts involved in quantitative genetics. The other options, while numerical values derived from the same principle of variance, do not appropriately correlate with the correlation coefficient of 0.7 when squared, as they yield incorrect figures that do not reflect the genetic influence on the trait accurately.