A recessive condition affects 1 in 2500 births, and the population is in Hardy-Weinberg equilibrium. What is the approximate carrier frequency?
Answer and explanation
Correct answer: C. About 1 in 25
- Step 1: Disease frequency q squared is 1/2500, so q is 1/50, or 0.02. Step 2. Carrier frequency is 2pq, which is 2 x 0.98 x 0.02 = 0.0392, or about 1 in 25. Answer: About 1 in 25. Why not the others: One in 50 is the allele frequency, not the carrier frequency. One in 100 and 1 in 625 do not follow from the calculation.
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