Question

Which Type of Hyperlipidemia is mostly related to defective LDL-receptors? What could be defective in Type IIb? Which lipoproteins are elevated in Type IIa and which are elevated in Type IIb?

a) Type IIa; Defective Apo E; Type IIa: LDL; Type IIb: VLDL
b) Type IIb; Defective Apo B-100; Type IIa: VLDL; Type II

b: LDL
c) Type IIa; Defective LDLR; Type IIa: HDL; Type IIb: LDL
d) Type IIb; Defective Apo A-I; Type IIa: LDL; Type IIb: HDL

Answer 1

Type IIa hyperlipidemia is related to defective LDL receptors, with elevated LDL levels. Type IIb may have defects leading to decreased LDL clearance or overproduction of lipoproteins, with both LDL and VLDL elevated.

Step-by-step explanation:

The type of hyperlipidemia that is mostly related to defective LDL receptors is Type IIa. This is known as Familial hypercholesterolemia, characterized by high levels of LDL cholesterol due to a mutation in the LDL receptor gene or the ApoB gene. In Type IIb, also known as combined hyperlipoproteinemia, there may be defects leading to the decreased clearance of LDL, and VLDL levels are high due to overproduction of substrates, including triglycerides and acetyl CoA, and an increase in B-100 synthesis.

In Type IIa, the primary lipoprotein that is elevated is LDL. In Type IIb, both LDL and VLDL are elevated. So, the correct details are as follows: Type IIa hyperlipidemia is mostly related to defective LDL receptors; in Type IIb, one could expect a defect in the clearance of LDL or overproduction of lipoproteins; Type IIa presents elevated levels of LDL, while Type IIb shows elevated levels of both LDL and VLDL.