PGK1

The PGK1 gene provides instructions for making an enzyme called phosphoglycerate kinase. This enzyme is found in cells and tissues throughout the body, where it is involved in a critical energy-producing process known as glycolysis. During glycolysis, the simple sugar glucose is broken down to produce energy.

Phosphoglycerate kinase helps carry out a chemical reaction that converts a molecule called 1,3-diphosphoglycerate, which is produced during the breakdown of glucose, to another molecule called 3-phosphoglycerate. This reaction generates one molecule of adenosine triphosphate (ATP), which is the main energy source in cells.

Researchers suspect that phosphoglycerate kinase may have additional functions, although little is known about the other roles this enzyme may play in cells.

phosphoglycerate kinase deficiency - caused by mutations in the PGK1 gene

At least 18 mutations in the PGK1 gene have been found to cause phosphoglycerate kinase deficiency. In some affected individuals, this condition causes a shortage of red blood cells (chronic hemolytic anemia) with or without neurological symptoms. In others, the condition is characterized by muscle weakness and cramping.

Most PGK1 gene mutations change single protein building blocks (amino acids) in phosphoglycerate kinase. A few other types of mutations, including insertions and deletions of a small amount of DNA in the PGK1 gene, have also been reported. Studies suggest that PGK1 gene mutations reduce the activity of phosphoglycerate kinase, which disrupts normal energy production and leads to cell damage or cell death. It is unclear why this abnormality preferentially affects red blood cells and brain cells in some people and muscle cells in others. Researchers speculate that different PGK1 gene mutations may have varying effects on the activity of phosphoglycerate kinase in different types of cells.