Phenotype as an Indicator of Genotype
Phenotype is a good indicator of genotype when the heritability of a trait is-
- High — Correct Answer
- Low
- Medium
- Zero
Explanation:
Correct Answer: High
When heritability (h²) is high, the additive genetic variance (VA) constitutes a large proportion of the total phenotypic variance (VP). This means environmental variance (VE) is relatively small, so the observed phenotype closely and reliably mirrors the animal's true genetic makeup (breeding value).
Heritability and Phenotype-Genotype Relationship
| h² Level | Phenotype as Indicator of Genotype | Best Selection Method |
|---|---|---|
| High (>0.40) | Good/Reliable indicator | Individual selection, Pedigree selection |
| Medium (0.20–0.40) | Moderate indicator | Combination of methods |
| Low (<0.20) | Poor indicator | Progeny testing, Family selection |
Practical Implications
- High h² → individual selection effective → rapid genetic progress
- Low h² → environment masks genotype → use progeny testing to average out environmental noise
- h²N = rAP² (squared correlation between additive genotype and phenotype)
📚 About this Topic — Animal Genetics & Breeding
This multiple choice question is from Animal Genetics & Breeding, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Genetics & Breeding to strengthen your preparation.
