Phosphoglycerate kinase deficiency is a genetic disorder that affects the body's ability to break down the simple sugar glucose, which is the primary energy source for most cells. Researchers have described two major forms of the condition. The most common form is sometimes called the hemolytic form. It is characterized by a condition known as chronic hemolytic anemia, in which red blood cells are broken down (undergo hemolysis) prematurely. Chronic hemolytic anemia can lead to unusually pale skin (pallor), yellowing of the eyes and skin (jaundice), fatigue, shortness of breath, and a rapid heart rate. Some people with the hemolytic form also have symptoms related to abnormal brain function, including intellectual disability, seizures, and stroke.

Phosphoglycerate kinase deficiency is caused by mutations in the PGK1 gene. This gene provides instructions for making an enzyme called phosphoglycerate kinase, which is involved in a critical energy-producing process in cells known as glycolysis. During glycolysis, the simple sugar glucose is broken down to produce energy.

Phosphoglycerate kinase deficiency appears to be a rare disorder. About 30 families with affected members have been reported in the scientific literature.

This condition is inherited in an X-linked recessive pattern. The PGK1 gene is located on the X chromosome, which is one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a mutation would have to occur in both copies of the gene to cause the disorder. Females with one altered PGK1 gene, however, may have some features of phosphoglycerate kinase deficiency, such as anemia. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.

Published Date: December 01, 2011
Published By: National Institutes of Health