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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A 25-year-old man requests cholesterol screening because of a family history of premature coronary artery disease (CAD). His lipid levels reveal an elevated total and LDL cholesterol. The high-density lipoprotein (HDL) and triglyceride values are normal. His physical examination is completely normal. Which of the following is the most common cause of genetic dyslipidemia?
assistant
The correct answer is  Familial combined hyperlipidemia has an incidence of 1/100. It is an autosomal dominant disorder and different affected family members may display different dyslipidemic phenotypes. Familial hypercholesterolemia (1/500) and familial defective Apo B (1/1000) are also common. The other two disorders (Apo C-II deficiency and lipoprotein lipase deficiency) are extremely rare.