<prompt> 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?familial combined hyperlipidemiafamilial hypercholesterolemiafamilial defective Apo BApo C-II deficiency  <response>: Familial combined hyperlipidemia has an incidence of 1100. It is an autosomal dominant disorder and different affected family members may display different dyslipidemic phenotypes. Familial hypercholesterolemia 1500 and familial defective Apo B 11000 are also common. The other two disorders Apo C-II deficiency and lipoprotein lipase deficiency are extremely rare. 