Genomic structure, chromosomal localization and expression of the human LIM-homeobox gene LHX5

The LIM-homeobox gene Lhx5 plays an essential role in the regulation of neuronal differentiation and migration during development of the central nervous system. Mice lacking Lhx5 function show severely disorganized brain morphology and are impaired in cognition and motor coordination. In this study, we characterized the cDNA and genomic organization of the human LHX5 gene and analyzed its expression and chromosomal location. The human gene was found to contain five exons encoding a protein composed of 402 amino acids that is 98.8% identical to mouse Lhx5. By reverse transcriptase polymerase chain reaction, LHX5 transcripts were detected in fetal brain and in various regions of the adult central nervous system including the spinal cord, the thalamus, and the cerebellum. Fluorescence in situ hybridization mapped the LHX5 gene to chromosome 12, position 12q24.31-24.32. These results provide a framework for future analysis of possible association of human hereditary disorders with mutations in LHX5.