Molecular Biology/Genetics USMLE Step 1 Practice Question
A 19 year old woman presents with episodic muscle weakness and exercise intolerance. She has a history of sensorineural hearing loss and migraine like headaches. Her mother and maternal uncle have similar symptoms, but her father is unaffected and none of his relatives are affected. Which of the following best explains the inheritance pattern of this disorder?
Answer choices
- AX linked recessive transmission
- BMitochondrial inheritance due to mutation in maternal mitochondrial DNACorrect answer
- CAutosomal recessive unmasking through consanguinity
- DGenomic imprinting with paternal silencing
- EAutosomal dominant mutation with variable penetrance
- FAutosomal dominant with complete penetrance
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