Lipid Biochemistry USMLE Step 1 Practice Question
A 34-year-old woman with family history of premature coronary artery disease presents with elevated lipids. Vital signs are normal; BP 118/76 mmHg, HR 72/min, RR 14/min. Laboratory studies show LDL cholesterol 180 mg/dL, apoB-100 150 mg/dL (normal <100), and triglycerides 95 mg/dL. LDL receptor binding is normal on functional testing. She denies statin use. No xanthomas are present on examination. Which genetic condition best explains her lipid profile?
Answer choices
- AFamilial defective apolipoprotein B-100Correct answer
- BPCSK9 gain-of-function mutation
- CFamilial hypoalphalipoproteinemia
- DLipoprotein(a) hyperlipoproteinemia
- EFamilial hypercholesterolemia
- FAutosomal recessive hypercholesterolemia (LDLRAP1 deficiency)
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