Lecture 5

Question 1

What happens to allele frequencies if a population is at HWE?

Answer 1

the allele frequencies in a population do not change between generations

Question 2

What type of mating yields predictable equilibrium genotype frequencies?

Answer 2

the simplest mating system, random mating

Question 3

What does a single generation of random mating establish?

Answer 3

HWE proportions of genotype frequencies

Question 4

What are the 5 HWE assumptions?

Answer 4

1. There is no selection (all individuals have equal probabilities of survival and reproduction)
2. there is no mutation (genes do not change from one allelic state to another)
3. there is no migration (genes are not added from outside the population)
4. there are no chance events (population is infinietly large)
5. there is random mating

Question 5

What do allele frequencies in a population always add to?

Answer 5

always sum to one

Question 6

What is the primary uses of the HWE principle?

Answer 6

• enables us to compute genotype frequencies from generation to generation
• serves as a null model in tests for evolution, by comparing observed to expected genotype frequencies
• forensic analysis

Question 7

What does violation of HWE expectation mean?

Answer 7

means one of the assumptions is not holding true

Question 8

Where are rare alleles primarily found?

Answer 8

in heterozygotes

Question 9

When a mutation arises, what type of form is it usually in?

Answer 9

when a mutation arises, it is rare, and almost always in the heterozygote form

Question 10

When is the amount of heterozygosity maximized?

Answer 10

when the allele frequencies are intermediate