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How do genetic defects in lipoprotein receptors promote atherosclerosis?

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The role of coronary artery disease in heart attack — cardiovascular disease This micrograph shows a cross section of a coronary artery narrowed by an atherosclerotic plaque (purplish matter inside the artery). Most heart attacks are caused by the rupture of an atherosclerotic plaque, which triggers the formation of a clot that abruptly blocks blood flow to part of the heart muscle.

Genetic defects in lipoprotein receptors, such as those seen in familial hypercholesterolemia, promote atherosclerosis by disrupting the body's ability to clear low-density lipoproteins (LDLs) from the bloodstream.12

Under normal conditions, cells use specific surface receptors to bind and internalize LDL particles, effectively removing them from circulation. When these receptors are deficient or dysfunctional due to mutations in the LDLR gene, LDL cholesterol cannot be moved into cells and instead accumulates in the blood. This elevated concentration of circulating LDL leads to its deposition within the endothelial lining of arteries.31245

Furthermore, these genetic defects disrupt internal feedback mechanisms. Normally, the uptake of cholesterol signals cells to cease further cholesterol synthesis; without functional receptors, this feedback inhibition is lost, causing cells to produce excessive amounts of cholesterol. The resulting high blood cholesterol levels accelerate the formation of fatty streaks and atherosclerotic plaques, which thicken and harden arterial walls, significantly increasing the risk of cardiovascular disease, heart attack, and stroke.124