solute carrier family 22 member 5
The SLC22A5 gene provides instructions for making a protein called OCTN2 that is found in the heart, liver, muscles, kidneys, and other tissues. This protein is positioned within the cell membrane, where it transports a substance known as carnitine into the cell. Carnitine is mainly obtained from the diet and is needed to bring certain types of fats (fatty acids) into mitochondria, the energy-producing centers within cells. Fatty acids are a major source of energy for the heart and muscles. During periods without food (fasting), fatty acids are also an important energy source for the liver and other tissues.
More than 60 mutations in the SLC22A5 gene have been found to cause primary carnitine deficiency. Some of these mutations create a premature stop signal in the instructions for making the OCTN2 protein, resulting in an abnormally short, nonfunctional protein. Other mutations change single protein building blocks (amino acids) in the OCTN2 protein.
Mutations in the SLC22A5 gene result in an absent or dysfunctional OCTN2 protein. As a result, there is a shortage (deficiency) of carnitine within cells. Without carnitine, fatty acids cannot enter mitochondria and be used to make energy. Reduced energy production can lead to some features of primary carnitine deficiency, such as muscle weakness and hypoglycemia. Fatty acids may also build up in cells and damage the heart, liver, and muscles. This abnormal buildup causes the other signs and symptoms of the disorder.
- high-affinity sodium dependent carnitine cotransporter
- novel organic cation transporter 2
- organic cation transporter 5
- organic cation/carnitine transporter 2
- solute carrier family 22 (organic cation transporter), member 5
- solute carrier family 22 (organic cation/carnitine transporter), member 5