Calculating Allele Frequency in Multiple Allelism
In a multiple allelic system with 3 alleles ($A_{1}, A_{2} & A_{3}$) If $A_{1}=0.25$, $A_{2}=0.35$ then frequency of $A_{3}$ will be-
- 0.25
- 0.35
- 0.40 — Correct Answer
- 0.10
Explanation:
Correct Answer: 0.40
In a multiple allelic system, all allele frequencies must sum to 1:
A₁ + A₂ + A₃ = 1
0.25 + 0.35 + A₃ = 1 → A₃ = 1 − 0.60 = 0.40
Multiple Allelism — Key Facts
| Feature | Detail |
|---|---|
| Definition | More than two alternative forms of a gene at the same locus |
| Origin | Produced by mutation |
| Found in | Population (not in a single individual) |
| Possible genotypes formula | N(N+1)/2, where N = no. of alleles |
Examples of Multiple Allelism
- ABO blood group in human — 3 alleles (IA, IB, IO)
- Coat colour in Rabbit — 4 alleles
- Eye colour in Drosophila — 15 alleles
H-W Principle for Multiple Alleles
- Sum of all allele frequencies at one locus = 1: p₁ + p₂ + p₃ + ... = 1
📚 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.