PRPS1 encodes an enzyme that catalyzes the phosphoribosylation of ribose 5-phosphate to 5-phosphoribosyl-1-pyrophosphate, which is necessary for purine metabolism and nucleotide biosynthesis. Defects in this gene are a cause of phosphoribosylpyrophosphate synthetase superactivity, Charcot-Marie-Tooth disease X-linked recessive type 5 and Arts Syndrome.

The deduced PRPS1 protein has 318 amino acids and shares 95% amino acid homology with PRPS2.PRPS1 amino acid sequence shows an exceptionally high degree of conservation, with homologies greater than 95% across different species from zebrafish to human.