Population Genetics MCAT Practice Question
A 28-year-old woman of Ashkenazi Jewish descent is found to be a carrier of the HEXA mutation (Tay-Sachs disease) on routine genetic screening. Tay-Sachs is an autosomal recessive lysosomal storage disorder with an incidence of 1 in 3,600 live births in this population. She is concerned about her reproductive risk and asks about the frequency of carriers like herself. Assuming Hardy-Weinberg equilibrium applies to the Ashkenazi Jewish population, which of the following best approximates the frequency of heterozygous carriers for the HEXA mutation?
Answer choices
- AApproximately 0.0017
- BApproximately 0.017
- CApproximately 0.053Correct answer
- DApproximately 0.50
- EApproximately 0.0003
- FApproximately 0.00017
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