A patient was found to have high LDL, increased total cholesterol. But normal levels of LDL-Receptors. What is the most probable cause:: (A) Apo B100 mutation, (B) Apo E defect, (C) LCAT Deficiency, (D) Lipoprotein lipase Deficiency
Answer is A. This is Familial defective Apo B100, also known as Autosomal Dominant Hypercholesterolemia IIa. There is a mutation in the gene encoding Apo B100, specifically in LDL-receptor binding domain of Apo B100.