The study on the nucleotide sequences of the RH genes and the Rh genotyping.

对Rh血型的分子分析显示了以下结果。(1)RHD和RHCE基因的核苷酸序列已基本确定。(2)RHD和RHCE基因间间隔区的核苷酸序列测定已接近完成。(3)我们在RHD和RHCE基因的内含子8中发现了简单重复序列多态性，这两个基因都含有5 bp的重复单元（AAAAT）n。短串联重复序列（STR）的多态性表明，RhD阴性的RHD基因可能是由DCe单倍型突变引起的，该突变使RHD基因消失。基于这些发现，STR多态性可能揭示RH单倍型的分子进化。(4)我们证明了导致D^基因型的杂合RHD-CE-D基因的基因组组织<va>，并表明D^<va>基因是由RHD和RHCE基因在相对小的区域内的基因转换产生的。这项研究还揭示了一个新的部分D的存在与D^<va>表型相关，我们称之为D^<va>样表型。(5)分子生物学分析表明，先证者的RHAG-cDNA中有122 bp的缺失，这是一个纯合性剪接突变。在骨髓增生异常综合征（MDS）患者中，Rh系统的表型从D（+）、C（+）、c（+）、E（+）、e（+）改变为D（-）、C（-）、c（+）、E（-），e（+），其原因可能与RHD和RHCE基因微缺失有关。

The molecular analyses on the Rh blood group showed the following results.(1) The nucleotide sequences of RHD and RHCE genes were almost determined.(2) The nucleotide-sequencing of the spacer region between the RHD and RHCE genes was nearly finished.(3) We identified simple sequence repeat polymorphism in intron 8 of the RHD and RHCE genes, both of which contained the 5bp repeat unit, (AAAAT)n in loci. The polymorphisms of this short tandem repeat (STR) suggests that the RhD-negative with a non-functional RHD gene might have arisen from DCe haplotype via mutation, which abolished the RHD gene. Based on these findings, the STR polymorphisms may shed light upon the molecular evolution of RH haplotype.(4) We demonstrated a genomic organization of the hybrid RHD-CE-D gene leading to the D^<va> jthenotype, and showed that the D^<va> gene was generated from gene conversion between the RHD and RHCE genes in relatively small regions. This study also revealed that the presence of a new partial D associated with the D^<va> phenotype, which we termed the D^<va>-like phenotype.(5) In a propositus with the Rhnull phenotype, the molecular analyses showed a deletion of 122bp in the RHAG-cDNA, which was revealed to be due to a homozygous splicing mutation. This result confirms that the RHAG gene is the most likely candidate for the regulator gene of Rhnufl cases.In a patient with myelodysplastic syndrome (MDS), the phenotype of the Rh system altered from D(+), C(+), c(+), E(+), e(+) to D(-), C(-), c(+), E(-), e(+) according to the progression of MDS.Its reason was demonstrated to be microdeletion containing the RHD and RHCE genes.