Metabolism USMLE Step 1 Practice Question
A 32-year-old woman presents with progressive difficulty releasing objects after gripping and daytime somnolence. Vital signs: BP 118/76, HR 82, RR 16, Temp 37°C, SpO2 98%. Examination reveals frontal balding, bilateral cataracts, and delayed muscle relaxation after handgrip test. Serum creatine kinase is mildly elevated at 450 U/L. She denies weakness. Her newborn son is hypotonic and weak with poor feeding. Expansion of which of the following trinucleotide repeats is most likely present in this family?
Answer choices
- ACAA
- BCGG
- CCAG
- DGAA
- ECTGCorrect answer
- FGGC
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