The Phosphoglycerate Kinase 1 is a glycolytic enzyme that catalyzes the conversion of 1,3-diphosphoglycerate to 3-phosphoglycerate. The encoded protein may also act as a cofactor for polymerase alpha. This gene lies on the X-chromosome, while a related pseudogene also has been found on the X-chromosome and another on chromosome 19.PGK1 is distinguished from testicular PGK2, which maps to chromosome 6p21.

The deduced protein contains 417 amino acid residues. Southern blot analysis of human genomic DNAs showed a complex pattern of hybridizing fragments, 2 of which were non-X in origin. The results were interpreted as reflecting the existence of a small family of dispersed PGK or PGK-like genes.