Molecular Biology/Genetics USMLE Step 1 Practice Question
A family has a history of genetic disease with an autosomal dominant pattern of inheritance. DNA from the grandfather (who is heterozygous for the disease) is cloned and used to construct a restriction map of the gene region involved in the disease. He has a restriction site polymorphism at EcoHV site 2 (HV-2), which is useful as a marker. His abnormal chromosome lacks the HV-2 site. DNA from his affected grandson is digested with EcoHV, Southern blotted, and probed with 32P-cDNA complementary to exon 2. Which of the following options most likely represents the restriction fragment length polymorphism (RFLP) pattern obtained from the affected grandson?
Answer choices
- ABCorrect answer
- BD
- CC
- DE
- EA
- FF
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