Glycine receptors are ligand-gated chloride channels. Channel opening is triggered by extracellular glycine. Channel opening is also triggered by taurine and beta-alanine. Channel characteristics depend on the subunit composition; heteropentameric channels are activated by lower glycine levels and display faster desensitization (By similarity). Plays an important role in the down-regulation of neuronal excitability (PubMed:11178872). Contributes to the generation of inhibitory postsynaptic currents. Channel activity is potentiated by ethanol (By similarity). Potentiation of channel activity by intoxicating levels of ethanol contribute to the sedative effects of ethanol (By similarity). Homopentamer (in vitro). Interacts with GLRB to form heteropentameric channels; this is probably the predominant form in vivo. Heteropentamer composed of two GLRA1 and three GLRB. Heteropentamer composed of three GLRA1 and two GLRB. Both homopentamers and heteropentamers form functional ion channels, but their characteristics are subtly different. Detected on spinal cord neurons (at protein level). Detected in spinal cord. The channel pore is formed by pentameric assembly of the second transmembrane domain from all five subunits. Channel opening is effected by an outward rotation of the transmembrane domains that increases the diameter of the pore. Defects in GLRA1 are the cause of inherited congenital myoclonus of Poll Hereford calves. It is an autosomal recessive disease characterized by hyperesthesia and myoclonic jerks of the skeletal musculature that occur both spontaneously and in response to sensory stimuli. The alpha subunit binds strychnine. Belongs to the ligand-gated ion channel (TC 1.A.9) family. Glycine receptor (TC 1.A.9.3) subfamily. GLRA1 sub-subfamily.