A population has two possible alleles for a gene: W and w. The w allele occurs with a frequency of 0.84 in a population of clams. Give the frequency of the homozygous dominant genotype.

a. 0.16

b. 0.267

c. 0.026

d. 0.84

e. 0.706

c. 0.026

Explanation:

Suppose the population is in Hardy-Weinberg equilibrium. According to it,

p + q = 1

p² + 2pq + q² = 1

where p = frequency of dominant allele

q = frequency of recessive allele

p² = frequency of homozygous dominant genotype

q² = frequency of homozygous recessive genotype

2pq = frequency of heterozygous genotype

Here, q = w = 0.84

p = W = 1 - w = 1 - 0.84 = 0.16

W² = 0.16 * 0.16 = 0.0256 = 0.026

Hence, frequency of the homozygous dominant genotype = 0.026