Biostatistics & Study Design USMLE Step 1 Practice Question
A 45-year-old man with no significant past medical history undergoes genetic screening as part of a research study investigating protective factors against hereditary hemochromatosis. The study identifies three independent genetic loci that, when all three protective alleles are present together, significantly reduce iron absorption and prevent clinical disease manifestation. The frequency of the protective allele at locus 1 is 0.6, at locus 2 is 0.2, and at locus 3 is 0.1 in the general population. Assuming Hardy-Weinberg equilibrium and independent assortment of these three loci on separate chromosomes, what is the probability that a randomly selected individual from this population will inherit protective alleles at all three loci?
Answer choices
- A0.9
- B0.36
- C0.12
- D0.048
- E0.012Correct answer
- F0.003
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