This gene encodes a member of the uridine diphosphoglucuronosyltransferase protein family. The encoded enzyme catalyzes the transfer of glucuronic acid from uridine diphosphoglucuronic acid to a diverse array of substrates including steroid hormones and lipid-soluble drugs. This process, known as glucuronidation, is an intermediate step in the metabolism of steroids. Two transcript variants encoding different isoforms have been found for this gene. While both isoforms are targeted to the endoplasmic reticulum, only the longer isoform appears to be active. [provided by RefSeq, May 2011]