UDP-Galactose-4-Epimerase; Short Chain Dehydrogenase/Reductase Family 1E, Member 1; UDP-N-Acetylgalactosamine 4-Epimerase; UDP-N-Acetylglucosamine 4-Epimerase; Galactose-4-Epimerase, UDP-; UDP-Glucose 4-Epimerase; UDP-GalNAc 4-Epimerase; UDP-GlcNAc 4-Epimerase

This gene encodes UDP-galactose-4-epimerase which catalyzes two distinct but analogous reactions: the epimerization of UDP-glucose to UDP-galactose, and the epimerization of UDP-N-acetylglucosamine to UDP-N-acetylgalactosamine. The bifunctional nature of the enzyme has the important metabolic consequence that mutant cells (or individuals) are dependent not only on exogenous galactose, but also on exogenous N-acetylgalactosamine as a necessary precursor for the synthesis of glycoproteins and glycolipids. Mutations in this gene result in epimerase-deficiency galactosemia, also referred to as galactosemia type 3, a disease characterized by liver damage, early-onset cataracts, deafness and cognitive disability, with symptoms ranging from mild ('peripheral' form) to severe ('generalized' form). Multiple alternatively spliced transcripts encoding the same protein have been identified.