Population Genetics

Question 1

1. Define the field of population genetics and explain why “population-field” has relevance to doctors who often treat just “one patient” at a time.

Answer 1

Population genetics: the study of allele (mutation) frequencies and changes in allele (mutation) frequencies in populations

• important for understanding frequency, how they change
• can lead to estimates of allele frequency if underlying genetic mechanism is known (dominant vs recessive, autosomal vs sex linked)

Question 2

2. Use basic principles of population genetics (estimate mutation rates, determine fitness, and understand effects of consanguinity and the addition of new mutations to gene pool).

Answer 2

Basic population gene principles:

mutation rate: take number of new cases, divide by total population, multiple by 2 (2 genes)
fitness
consanguniity

can also find carrier frequency of autosomal recessive diseases: take prevalance (q^2), take square root for q

can get carrier rate (but unaffected) by plugging into 2pq

q+p=1 (I think)

Question 3

3. Explain the assumptions required for Hardy-Weinberg principle to apply.

Answer 3

population is large
mating is random
allele frequencies are not changing over time; no selection, no new mutations

violated constantly, but differences are modest enough that we dont care

Question 4

4. Apply the Hardy-Weinberg principle to estimate carrier frequencies for autosomal recessive disorders.

Answer 4

can also find carrier frequency of autosomal recessive diseases: take prevalance (q^2), take square root for q

can get carrier rate (but unaffected) by plugging into 2pq

q+p=1 (I think)

Question 5

5. Discuss how physicians managing genetic diseases could affect the prevalence of genetic diseases.

Answer 5

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