CPT1A

The CPT1A gene provides instructions for making a liver enzyme called carnitine palmitoyl transferase I. This enzyme assists in the transport of certain fats, called long-chain fatty acids, into the energy-producing centers in the cell (mitochondria). This process is necessary for these fats to be broken down for energy. Long-chain fatty acids must be joined to a naturally occurring substance called carnitine for entry into the mitochondria. Carnitine palmitoyl transferase I connects the long-chain fatty acids to carnitine to promote this transport process.

carnitine palmitoyltransferase I deficiency - caused by mutations in the CPT1A gene

More than 20 mutations responsible for carnitine palmitoyltransferase I deficiency have been identified in the CPT1A gene. Most of these mutations lead to the improper substitution of one amino acid (a building block of proteins) for another amino acid in carnitine palmitoyl transferase I. These mutations reduce or eliminate the ability of this enzyme to transport long-chain fatty acids into the mitochondria for energy production. As a result, the ability of cells to use these fats for energy is greatly reduced, leading to the signs and symptoms of this disorder such as weakness, an enlarged liver (hepatomegaly), and low blood sugar (hypoglycemia).

other disorders - associated with the CPT1A gene

CPT1A mutations appear to increase the risk of a serious liver disorder that can develop in women during pregnancy. This disorder, acute fatty liver of pregnancy, begins with abdominal pain and can rapidly progress to liver failure. Signs of acute fatty liver of pregnancy include an abnormal accumulation of fat in the liver, low blood sugar (hypoglycemia), increased levels of ammonia in the blood (hyperammonemia), and abnormalities in liver enzymes. A small percentage of women who have a mutation in one copy of the CPT1A gene in each cell and are carrying a fetus with mutations in both copies of the CPT1A gene develop this maternal liver disease.