Consider a population of 20 aa, 32 Aa, and 48 AA individuals. Selection acts against the lethal recessive homozygote (aa) before adulthood. After selection, survivors mate randomly. What are the genotypic frequencies of the next generation?
A) 25% aa, 50% Aa, and 25% AA
B) All AA
C) 4% aa, 16% Aa, and 64% AA
D) None of the above.

Question

Quizplus · Accepted Answer

After selection, the frequency of aa individuals will be reduced, but the frequencies of the other genotypes will remain the same. The frequency of A alleles, p, can be calculated as (2 x 48 + 32) / (2 x 20 + 2 x 32 + 2 x 48) = 0.6. The frequency of a alleles, q, will be 1 - 0.6 = 0.4. The frequency of AA individuals in the next generation will be p^2 = 0.6^2 = 0.36 or 36%, the frequency of Aa individuals will be 2pq = 0.48 or 48%, and the frequency of aa individuals will be q^2 = 0.16 or 16%. Therefore, the correct answer is C.

Consider a Population of 20 Aa, 32 Aa, and 48