Hepatic lipase deficiency

Hepatic lipase deficiency is a disorder that affects the body's ability to break down fats, leading to an imbalance of cholesterol and triglycerides in the blood.

Overview

Hepatic lipase deficiency is a disorder that affects the body's ability to break down fats (lipids). People with this disorder have increased amounts of triglycerides and cholesterol in the blood. These individuals also have increased amounts of molecules known as high-density lipoproteins (HDLs) and decreased amounts of molecules called low-density lipoproteins (LDLs). In people with this deficiency, the LDL molecules are often abnormally large.

Normally, high levels of HDL ("good cholesterol") and low levels of LDL ("bad cholesterol") are protective against the accumulation of fatty deposits on artery walls (atherosclerosis) and heart disease. However, some individuals with hepatic lipase deficiency develop atherosclerosis and heart disease in mid-adulthood, while others do not. It remains unclear whether these individuals have a greater risk of developing these conditions than the general population.

Frequency

Hepatic lipase deficiency is likely a rare disorder; only a few affected families have been reported in the scientific literature.

Causes

Hepatic lipase deficiency is caused by mutations in the LIPC gene. This gene provides instructions for making an enzyme called hepatic lipase. This enzyme is produced by liver cells and released into the bloodstream, where it helps convert very low-density lipoproteins (VLDLs) and intermediate-density lipoproteins (IDLs) to LDLs. The enzyme also assists in transporting HDLs that carry cholesterol and triglycerides from the blood to the liver for redistribution or removal.

LIPC gene mutations prevent the release of hepatic lipase or decrease the enzyme's activity. As a result, VLDLs and IDLs are not efficiently converted into LDLs, and HDLs carrying cholesterol and triglycerides remain in the bloodstream.

Gene Associated with Hepatic Lipase Deficiency

• LIPC

Inheritance

This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.