APOB Gene
The APOB gene provides instructions for making two versions of the apolipoprotein B protein, a short version called apolipoprotein B-48 and a longer version known as apolipoprotein B-100. Both proteins are components of lipoproteins, which are particles that carry fats and fat-like substances, such as cholesterol, in the blood. More than 120 mutations in the APOB gene have been found to cause familial hypobetalipoproteinemia (FHBL), a disorder that impairs the body’s ability to absorb and transport fat. Missense mutations in the LDL receptor-binding domain of apoB cause familial ligand-defective apoB-100, characterized by hypercholesterolemia and premature coronary artery disease. Other mutations in APOB can cause familial hypobetalipoproteinemia, characterized by hypocholesterolemia and resistance to atherosclerosis.
