Molecular Biology/Genetics USMLE Step 1 Practice Question
In the family shown below, individuals affected with profound deafness are represented by a shaded symbol. (Pedigree shows two couples in generation I and II with normal hearing producing a deaf child in generation III, along with other affected individuals.) Which of the following would best explain the phenotypes of individuals in the fourth generation?
Answer choices
- AX-linked dominant inheritance
- BAutosomal dominant inheritance
- CLocus heterogeneityCorrect answer
- DMitochondrial inheritance
- EMultifactorial inheritance
- FAutosomal recessive inheritance with incomplete penetrance
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