Familial Hypobetalipoproteinemia Associated with a Mutant Species of Apolipoprotein B (B-46)

Abstract

THE two plasma forms of apolipoprotein B—B-100 and B-48 — are important proteins in mammalian lipoprotein metabolism.1 Both are products of the same structural gene,2 which in humans is located on chromosome 2.3 4 5 Apolipoprotein B-100 is a glycoprotein containing 4536 amino acids;6 7 8 9 10 and it is synthesized by the liver.1 It is an important structural protein in very-low-density lipoproteins (VLDL), which are rich in triglycerides, and low-density lipoproteins (LDL), which are rich in cholesteryl esters. Apolipoprotein B-100 is virtually the only protein component of human LDL, and it is the ligand responsible for the recognition and uptake of LDL by cellular . . .