Consider a biallelic locus with alleles A₁ and A₂.A₁ mutates to A₂ with a forward mutation rate of 0.0000025.A₂ mutates back to A₁ with a reverse mutation rate of 0.0000010.What will be the equilibrium frequency of the A₁ allele?
A)0.0407
B)0.1298
C)0.1820
D)0.2857
E)0.3869

Question

Quizplus · Accepted Answer

The equilibrium frequency of A₁ allele can be calculated using the Hardy-Weinberg equation:
p² + 2pq + q² = 1
where p is the frequency of A₁ allele and q is the frequency of A₂allele.

At equilibrium, the forward mutation rate should be equal to the reverse mutation rate, i.e.,
μ(A₁ → A₂) = ν(A₂ → A₁)
0.0000025 = p × 0.0000010
p = 0.40

Therefore, q = 0.6
Substituting the values of p and q in the Hardy-Weinberg equation:
p² + 2pq + q² = 1
(0.40)² + 2(0.40)(0.60) + (0.60)² ≈ 0.28
So, the equilibrium frequency of the A₁ allele is 0.2857, which is closest to option D.

Consider a Biallelic Locus with Alleles A₁ and A₂