Bozeman Science: Solving Hardy Weinberg Problems
http://www.bozemanscience.com/solving-hardy-weinberg-problems
p2 + 2pq + q2 = 1
No Mutations
Conditions for determining the stability of a gene pool
Large Populations
Random Mating
No Migration
No Natural Selection
Alleles:
Dominant Allele:
Recessive Allele:
What’s the difference between calculating the percent of the population versus allele frequency?
Individual Phenotypes in a Population
Odds of having two recessive alleles?
Gene Pool = Frequency of Alleles
What is the frequency of each allele in the gene pool?
p = allele frequency of dominant traits
Odds of having two dominant alleles?
q = allele frequency of recessive traits
Odds of having one of each allele?
p2 + 2pq + q2 = 1
Solve the following Hardy Weinberg problems:
1. Sixteen percent of the population in unable to taste the chemical PTC. These non-tasters are
recessive for the tasting gene.
a. What percentage of the individuals in the population are tasters?
b. What is the frequency of the dominant and recessive allele?
c. What percentages of the population are heterozygous for the trait?
2. The delta – 32 mutation, a recessive gene, gives humans protection from HIV infection. The allele
frequency in a town in Sweden is 20%.
a. What percent of the population have two copies of the gene and are therefore immune to
HIV?
b. What percent of the population are less susceptible to the disease since they are
heterozygous?