The enzyme Uridine monophosphate synthase (EC 4.1.1.23, UMPS) (orotate phosphoribosyl transferase and orotidine-5'-decarboxylase) catalyses the formation of uridine monophosphate (UMP), an energy-carrying molecule in many important biosynthetic pathways.[5] In humans, the gene that codes for this enzyme is located on the long arm of chromosome 3 (3q13).[6]