The GABRB3 gene encodes a member of the ligand-gated ionic channel family. The encoded protein, GABA A Receptor beta 3, is one of at least 13 distinct subunits of a multisubunit chloride channel that serves as the receptor for gamma-aminobutyric acid, the major inhibitory transmitter of the nervous system. GABRB3 is located on the long arm of chromosome 15 in a cluster with two genes encoding related subunits of the family. Mutations in the GABA A Receptor beta 3 gene may be associated with the pathogenesis of Angelman syndrome, Prader-Willi syndrome, and autism.