A-B lipoproteinemia is characterized by a deficiency of which apoprotein?

A-B lipoproteinemia is characterized by a deficiency of apolipoprotein B (ApoB). This condition primarily affects lipid transportation in the body. ApoB is crucial for the assembly and secretion of lipoproteins, specifically very-low-density lipoprotein (VLDL) and low-density lipoprotein (LDL), which are essential for transporting triglycerides and cholesterol in the bloodstream.

Without sufficient levels of ApoB, the body cannot effectively transport these lipids, leading to abnormal lipid accumulation and associated metabolic problems. This deficiency can result in symptoms such as fat malabsorption and the presence of lipid-laden enterocytes in the intestine. Understanding the role of ApoB in lipid metabolism is fundamental to grasping how deficiencies in specific apolipoproteins can lead to various metabolic disorders.