GABA (GAMMA-AMINOBUTYRIC-ACID) NEUROTRANSMISSION - IDENTIFICATION ANDFINE MAPPING OF THE HUMAN GABA(B) RECEPTOR GENE

GABA (gamma-amino-butyric acid) receptors are a family of proteins inv olved in the GABAergic neurotransmission of the mammalian central nerv ous system (CNS). They have physiological importance and clinical rele vance in several diseases. We report the identification, cloning, and fine mapping of the human cDNA for GABA, receptor. A 4.2-Kb cDNA conta ining an open reading frame for a predicted protein of 960 aa was isol ated from a fetal brain cDNA library. It had a strong identity (91.5%) with the rat GABA, receptor (rGB1A) nucleotide sequence, that corresp onded to 98.6%, identity at the amino acid level. Expression of the GA BA(B) at the transcription level was detected by Northern analysis in all brain areas examined. The GABA,receptor has been mapped to human c hromosome 6p21.3 within the HLA class I region close to the HLA-F gene . Susceptibility loci for multiple sclerosis, epilepsy, and schizophre nia have been suggested to map in this region. (C) 1998 Academic Press .