The frequency of the Hemoglobin A allele is 0.9.The heterozygote with the recessive allele, s, shows resistance to the malarial parasite.What is the frequency of the heterozygote for the pair As?
A)0.81
B)0.1
C)0.01
D)0.18
E)0.09

Question

Quizplus · Accepted Answer

The frequency of the A allele is given as 0.9, which means that the frequency of the recessive s allele would be (1-0.9) = 0.1.

The heterozygote for the pair As would be Aa (where A represents the dominant allele for normal hemoglobin, and a represents the recessive allele for sickle cell anemia).

We know that the heterozygote Aa shows resistance to the malarial parasite.

So, to find the frequency of the Aa heterozygote, we can use the Hardy-Weinberg equation:

p^2 + 2pq + q^2 = 1

where p is the frequency of the A allele, q is the frequency of the a allele, and pq is the frequency of the heterozygote.

Substituting the values, we get:

0.9^2 + 2(0.9)(0.1) + 0.1^2 = 0.81

Therefore, the frequency of the heterozygote for the pair As is 0.81, which is option D.

The Frequency of the Hemoglobin a Allele Is 0