A large population of laboratory animals has been allowed to breed randomly for a number of generations. After several generations, 25% of the animals display a recessive trait (A2A2), the same percentage as at the beginning of the breeding program. The rest of the animals show the dominant phenotype, with heterozygotes indistinguishable from the homozygous dominants.
What is the estimated frequency of allele A1 in the gene pool?
A) 0.125
B) 0.25
C) 0.50
D) 0.75

Question

Quizplus · Accepted Answer

The frequency of the recessive allele (A2) is 0.5, since 25% of the population displays the recessive trait. The frequency of the dominant allele (A1) is therefore 1 - 0.5 = 0.5.

A Large Population of Laboratory Animals Has Been Allowed to Breed