GABA, the major inhibitory neurotransmitter in the vertebrate brain, mediates neuronal inhibition by binding to the GABA/benzodiazepine receptor and opening an integral chloride channel. Generally pentameric. There are five types of GABA(A) receptor chains: alpha, beta, gamma, delta, and rho. May be palmitoylated. This subunit carries the benzodiazepine binding site. Belongs to the ligand-gated ion channel (TC 1.A.9) family. Gamma-aminobutyric acid receptor (TC 1.A.9.5) subfamily. GABRG1 sub-subfamily.