The product of this gene belongs to the ligand-gated ionic channel (TC 1.A.9) family. It encodes the gamma-aminobutyric acid (GABA) A receptor which is a multisubunit chloride channel that mediates the fastest inhibitory synaptic transmission in the central nervous system. This gene encodes an epsilon subunit. It is mapped to chromosome Xq28 in a cluster comprised of genes encoding alpha 3, beta 4 and theta subunits of the same receptor. Alternatively spliced transcript variants have been identified, but only one is thought to encode a protein. [provided by RefSeq, Oct 2008]