You have sampled a population in which you know that the per

You have sampled a population in which you know that the percentage of the homozygous recessive genotype (aa) is 36%. Using that 36%, calculate the following: The frequency of the aa genotype. Estimate the frequency of the a allele. The frequency of the A allele. The expected frequencies of the AA and Aa genotypes.

Solution

a: Frequency of aa genotype (q²) = 0.36

b: Frequency of a allele (q)= square root of 0.36= 0.6

c: Frequency of A allele (p)=
p+q=1
so, p= 1-q
p= 1-0.6= 0.4

d: Expected frequency of
AA (p²)= (0.4)²= 0.16
and Aa genotypes (2pq)= 2 x 0.4 x 0.6= 0.48