Suppose you have a population of frogs in HW equilibrium tha
Suppose you have a population of frogs in HW equilibrium that have a single gene that codes for skin color. This gene has two alleles G for green and g for albino. Homozygous GG individuals are green. Heterozygous Individuals are green, and Homozygous gg individuals ate albino. You are told that the frequency of the g allele in this population of frogs is 0.1 What are the phenotype frequencies? The genotype frequencies? The allele frequencies? Out of 1000 frogs, how many are green? How many are albino? How many are earners for albinism?
Solution
Answer:
1. GG = Green, Gg = Green, gg = Albino
p2 + 2pq + q2 = 1
Given, frequency of g allele (q) = 0.1
p + q = 1
So, p (frequency of G allele) = 1 - 0.1 = 0.9
Phenotype frequencies:
Green = p2 + 2pq = (0.9)2 + 2 * 0.9 * 0.1 = 0.81 + 0.18 = 0.99
Albino = q2 = 1 - 0.99 = 0.01
Genotype frequencies:
p2 = (0.9)2 = 0.81 (Homozygous green)
2pq = 2 * 0.9 * 0.1 = 0.18 (Heterozygous green)
q2 = (0.1)2 = 0.01 (Albino)
Allele frequencies:
p (Frequency of G) = 0.9
q (Frequency of g) = 0.1
Out of 1000 frogs, (0.99 * 1000) = 990 are green.
Out of 1000 frogs, (0.01 * 1000) = 10 are albino.
Out of 1000 frogs, carriers of albinism = (2pq * 1000) = (2 * 0.9 * 0.1 * 1000) = (0.18 * 1000) = 180.
