Type of Gene Action Governing Polygenic Inheritance
Polygenic inheritance is governed by which type of gene action?
- Epistasis
- Over-dominance
- Dominance
- Additive gene action — Correct Answer
Explanation:
Correct Answer: Additive gene action
Polygenic inheritance (when one character is controlled by many genes/polygenes) is governed by additive gene action (AGA).
Additive Gene Action — Key Points
- Polygenic inheritance, general combining ability (GCA), and resemblance between relatives are all due to additive gene action.
- Additive gene action is exploited by selection.
- Traits governed by additive gene action do NOT show inbreeding depression.
- Economic traits (milk production, egg production, fat %, growth rate) are controlled by polygenes and are greatly affected by environment — they exhibit continuous variation.
Gene Action Types
| Type | Exploited by |
|---|---|
| Additive (AGA) | Selection; GCA; polygenic traits |
| Non-additive (NAGA) | Heterosis; SCA; Epistasis, Dominance, Over-dominance |
📚 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.
