Heritability from Full Sib Correlation
If correlation coefficient of full sib is 0.2 then find out the heritability of a trait-
- 0.2
- 0.4 — Correct Answer
- 0.8
- 0.16
Explanation:
Correct Answer: 0.4
For full siblings, the covariance equals ½VA + ¼VD + VEC. In practical estimations using intra-class correlation (t), the formula used is h² = 2t (assuming dominance and common environment are negligible).
Step-by-Step Calculation
- Given: Correlation coefficient of full sibs (t) = 0.2
- Formula for full sibs: h² = 2t
- h² = 2 × 0.2 = 0.4
Covariance of Relatives — Summary Table
| Relatives | Covariance | Heritability Formula |
|---|---|---|
| Offspring & one parent | ½VA | h² = 2b |
| Offspring & mid-parent | ½VA | h² = b |
| Half sibs | ¼VA | h² = 4t |
| Full sibs | ½VA + ¼VD + VEC | h² = 2t |
Why Other Options Are Wrong
- 0.2 → that is the raw correlation; h² formula requires multiplication by 2 for full sibs
- 0.8 → would be correct for half sibs (h² = 4t = 4 × 0.2 = 0.8); wrong formula applied here
- 0.16 → incorrect; 0.2² = 0.04, not a valid formula for this calculation
📚 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.
