Inbreeding Coefficients for Different Mating Systems
Inbreeding coefficient of progenies produced by selfing, parent-offspring mating, full sibs mating & half sibs mating during first generation are respectively-
- 0.5, 0.25, 0.25, 0.125 — Correct Answer
- 0.5, 0.50, 0.50, 0.125
- 0.5, 0.50, 0.25, 0.125
- 0.5, 0.25, 0.50, 0.125
Explanation:
Correct Answer: 0.5, 0.25, 0.25, 0.125
The Inbreeding coefficient (Fx) is the probability that two alleles at a randomly chosen locus are identical by descent (IBD). The formula is: Fx = ½ × Rxy (where Rxy = coefficient of relationship).
Inbreeding Coefficients — Summary Table
| Mating System | Coefficient of Relationship (Rxy) | Inbreeding Coefficient (Fx) |
|---|---|---|
| Selfing | 1.00 (100%) | 0.50 (50%) |
| Sire-daughter / Son-dam / Full-sib mating | 0.50 (50%) | 0.25 (25%) |
| Half-sib / Grandparent-grandoffspring / Double first cousin mating | 0.25 (25%) | 0.125 (12.5%) |
| Single first cousin mating | 0.125 (12.5%) | 0.0625 (6.25%) |
| Half first cousin mating | 0.0625 (6.25%) | 0.03125 (3.125%) |
Note on Inbred Lines
- An inbred line is developed from two generations of full-sib mating.
- Minimum inbreeding coefficient to call a line an inbred line = 0.375 (37.5%).
📚 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.
