Lipid Biochemistry USMLE Step 1 Practice Question
A 61-year-old woman with hyperlipidemia presents with corneal opacities and tendon xanthomas. Her lipid panel shows total cholesterol 520 mg/dL, LDL 380 mg/dL, and HDL 45 mg/dL. She has a family history of premature coronary artery disease and sudden cardiac death. Which of the following genetic mutations most likely explains this presentation?
Answer choices
- ALoss-of-function mutation in ABCA1 gene
- BGain-of-function mutation in apolipoprotein B gene
- CLoss-of-function mutation in lipoprotein lipase gene
- DGain-of-function mutation in PCSK9 gene
- ELoss-of-function mutation in LDL receptor geneCorrect answer
- FSitosterolemia from ABCG5 or ABCG8 mutation
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