Question

A gene locus has two alleles A, a. If the frequency of dominant allele A is 0.4, then what will be the frequency of homozygous dominant, heterozygous and homozygous recessive individuals in the population
A. 0.16 (M), 0.36 (Aa), 0.48 (aa)
B. 0.36 (M), 0.48 (Aa), 0.16 (aa)
C. 0.16 (M), 0.24 (Aa), 0.36 (aa)
D. 0.16 (M), 0.48 (Aa), 0.36 (aa)

Answer 1

Correct Answer - D
Frequency of dominant allele (p) = .4
Appling Hardy Weinberg equilibrium -
p + q = 1
q = 1 - .4 = .6
`p^2 + q^2 + 2pq = 1`
Frequency of homozygous dominant genotype `(p^2 // A A) = (.4)^2 = .16`
Frequency of Heterozygote `(2pq // Aa) = 2 xx .4 xx .6 = .48`
Frequency of homozygous recessive genotype `(q^2 // a a) = (.6)^2 = .36`