Factors Affecting Degree of Relationship
The degree of relationship between individuals in a population depends upon-
- Size of population
- Type of mating system
- Both a & b — Correct Answer
- Gene & genotype frequencies
Explanation:
Correct Answer: Both a & b
The degree of genetic relationship among individuals in a population is determined jointly by two factors: population size and the mating system practiced.
How Each Factor Affects Relationship
| Factor | Effect on Degree of Relationship |
|---|---|
| Size of population | Smaller population → fewer unrelated mates available → individuals forced to mate with relatives → higher average relationship; leads to inbreeding even with random mating |
| Type of mating system | Close breeding (full-sib, parent-offspring) → very high relationship (Rxy = 0.50); Line breeding → moderate (Rxy = 0.25); Out-crossing → minimal relationship; Panmixia (random mating) → maintains H-W equilibrium |
Coefficient of Relationship (Rxy) — Key Values
| Mating | Rxy | Fx (Inbreeding coefficient) |
|---|---|---|
| Full-sib / Parent-offspring | 0.50 | 0.25 |
| Half-sib / Double first cousin | 0.25 | 0.125 |
| Single first cousin | 0.125 | 0.0625 |
📚 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.
