Entire sequence of a mouse chromosomal segment containing the gene Rhced and a comparative analysis of the homologous...

The mouse genomic sequence of the region containing the gene Rhced, the orthologue to the human gene RH30, was determined to elucidate the structure of Rhced and its flanking regions and to compare these with the corresponding human genomic region. Two genes, Smp1 and AK003528 (an orthologue of FLJ10747), flank Rhced. Neither sequences homologous to the characteristic nucleotide elements flanking the RHD gene in humans (rhesus boxes) nor an additional Rh gene were found within the mouse region sequenced. This result and that of a previous report demonstrate that this chromosomal region of the mouse comprises five genes (FLJ10747-RHCE-SMP1-NPD014-P29) that exhibit syntenic homology with the corresponding human region, which suggests that the RHD gene and rhesus boxes were inserted later. Evaluations of tissue distribution and subcellular localization of these genes indicate that the SMP1 orthologue has a ubiquitous tissue distribution and cytoplasmic localization, whereas AK003528 is expressed slightly higher in testis with a strong subcellular localization in the nucleus. Despite the steady improvements in the draft sequence of the human genome, this study demonstrates the continuing benefits of comparative genetic analyses in increasing our understanding of human genomic structure.