Question

A snake population has a mutation that causes snakes to turn purple rather than green. it is found in 1/10,000 snakes in the general population. They are trying to determine the specific mutation rate of a snake population near a radiation field, 500 of these snakes where sampled and they found that 8 of them had the mutation. What is the mutation rate for the purple mutation in the radiation population? What would the frequency of the recessive allele be at equilibrium if the selection coefficient was 2.0?

Answer 1

Answer:

• Mutation rate in snake population = 1 / 10000
• Specific mutation rate of snake population nead a radiation field = ?
• Number of snakes sampled = 500
• Number of snakes in sample that had mutation = 8
• Mutation rate for the purple mutation in the radiation population = 8*20 / 10000 = 160 /10000

Frequency of the recessive allele at equilibrium if the selection coefficient was 2.0

• For deleterious recessives: q' = sqrt (u / s) Where:
  • q' = equilibrium frequency of the deleterious recessive allele
  • sqrt = the square root
  • u = mutation rate
  • s = selection coefficient
• equilibrium frequency of the deleterious recessive allele q' = sqrt (0.016 / 2) = 0.0894