The analysis of Rh antigen (polypeptide) function and the molecular evolution of orthologous RH genes in various species.

Levine和Stetson发现的Rh血型是临床上最重要的类似ABO系统的血型之一。结果表明，Rh系统编码于RHCE和RHD两个基因上，这两个基因紧密相连，高度同源，每个基因由10个外显子组成。RH基因位于染色体1p 34.3-36.1。许多血清学调查已经发现并鉴定了许多变异，如D-，部分D和抗原。RHD和RHCE基因长度分别为57295 bp和57831 bp。多次重组（和/或基因转换）、核苷酸替换、小核苷酸间隙、微卫星复制滑移、大核苷酸间隙（由于Alu序列）和RH基因之间高水平的同源性（%）是RH基因和RH变异形成和进化的重要因素。我们分析了Rh变异的弱d表型，并报道了它们的分子遗传背景。根据对这些Rh变异（弱d）的分析结果，我们推测了Rh抗原（多肽）的表达机制。据推测，人类Rh家族（超家族）由Rh （RHCE和RHD）、RHAG （rh50）、RHBG和RHGK （RHCG）基因组成。通过生化证据和Genbank检索推测Rh超家族与铵转运体有关。我们的系统发育树分析（邻居连接法）表明，来自铵转运体的RH、RHAG和RHBG/RHGK基因可能独立遵循不同的进化途径。通过对猪同源RH基因超家族的分析，我们确定猪RH和RHBG基因分别位于猪染色体6q22-q23和4q21-q22上。

The Rh blood group discovered by Levine and Stetson is clinically one of the most important blood groups similar to ABO system. It is indicated that the Rh system was encoded on two genes termed RHCE and RHD, which are closely linked, highly homologous and consist of ten exons each. The RH genes are located in chromosome 1p 34.3-36.1. Many serological investigations have revealed and a lot of variants such as D--, partial D and antigens from forty up were identified. The RHD and RHCE genes totalled 57295 bp and 57831 bp in length, respectively. It is thought that multiple recombination (and/or gene conversion), nucleotide substitutions, small nucleotide gaps, replication slippage of microsatellite, large nucleotide gaps (due to Alu sequence) and the high level of the homology(%) between both RH genes is the important factors in the formation and evolution of both RH genes and Rh variants.We analyzed weakD phenotypes, which are Rh variant, and reported the molecular genetic background of them. Due to the findings obtained by the analysis of these Rh variants(weakD), we speculated the mechanism of the expression of Rh antigen(polypeptide).It is presumed that human Rh family (superfamily) consists of the RH (RHCE and RHD), RHAG (RH5O), RHBG and RHGK (RHCG) genes. It is speculated that Rh superfamily is associated with ammonium transporter by biochemical evidence and Genbank search. The RH, RHAG and RHBG/RHGK genes derived from ammonium transporter might have independently followed different evolutionary pathways by our phylogenetic tree analysis(the neighbor-joining method).By analyzing the orthologous RH gene superfamily in pig, we determined the porcine RH and RHBG genes are mapped in pig chromosomes 6q22-q23 and 4q21-q22, respectively.