Molecular Biology/Genetics USMLE Step 1 Practice Question
A 28-year-old molecular biology researcher identifies a novel gene with a conserved 7-helix transmembrane domain motif in a patient with familial hypercholesterolemia. Laboratory analysis reveals elevated LDL cholesterol (285 mg/dL) and normal triglycerides. The patient denies statin use. Genetic sequencing confirms a mutation in the target gene. The researcher notes the encoded protein localizes to the cell membrane. Which of the following proteins is most likely encoded by this gene?
Answer choices
- AGlucose transporter
- BCystic fibrosis transmembrane conductance regulator channel
- CAdenylate cyclase
- DNa+/K+ ATPase
- EBeta-adrenergic receptor for epinephrineCorrect answer
- FLDL receptor for cholesterol uptake
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