Lipid Biochemistry USMLE Step 1 Practice Question
A 45-year-old man presents with xanthomas on his Achilles tendons and eyelids, along with corneal arcus. Laboratory studies show total cholesterol of 650 mg/dL and LDL of 520 mg/dL despite dietary modification. His father died of myocardial infarction at age 52. Which of the following genetic mutations is most likely responsible for this condition?
Answer choices
- ALoss-of-function mutation in CETP
- BGain-of-function mutation in PCSK9
- CMutation in the apoB-100 binding domain
- DDeficiency of lipoprotein lipase
- ELoss-of-function mutation in the LDL receptor geneCorrect answer
- FLysosomal acid lipase deficiency (cholesterol ester storage disease)
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