This gene encodes a member of the gamma-glutamyl transpeptidase (GGT) family, which are important in the metabolism of glutathione. The most ubiquitously expressed human GGT gene, GGT1, encodes a single transmembrane polypeptide that is post-translationally processed to form a heavy and a light chain. In contrast, the product of this gene only contains homology to the light chain region, and lacks a transmembrane domain. Multiple alternatively spliced variants, encoding the same protein, have been identified. [provided by RefSeq, Oct 2008].