Lipid Biochemistry USMLE Step 1 Practice Question
A 19-year-old man presents with severe chest pain and is found to have an acute myocardial infarction. His fasting lipid panel shows total cholesterol of 680 mg/dL, triglycerides of 920 mg/dL, and a dense band on lipoprotein electrophoresis. His father died of an MI at age 32. Which genetic defect is most consistent with this presentation?
Answer choices
- AHomozygous familial hypercholesterolemia (LDL receptor mutations)Correct answer
- BFamilial combined hyperlipidemia with genetic predisposition to early MI
- CType III hyperlipoproteinemia (apoE2/E2 genotype)
- DHeterozygous familial hypercholesterolemia with secondary hypertriglyceridemia
- EFamilial chylomicronemia syndrome with secondary atherosclerosis
- FType III hyperlipoproteinemia (familial dysbetalipoproteinemia)
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