ABSTRACT
<p><b>OBJECTIVE</b>To evaluate the status of eight RHD specific exons in 131 Han Chinese blood donors who were classified as RhD-negative by serological methods and explore the genomic structure of RHD gene among the Han Chinese. The Rh blood group system has the highest prevalence of polymorphisms among human blood group systems and is clinically significant in transfusion medicine. The Rh antigens are expressed on polypeptides encoded by two highly homologous genes, RHD and RHCE. Recent molecular studies have shown that the RhD-negative trait could be generated by multiple genetic mechanisms and is ethnic group-dependent.</p><p><b>METHODS</b>The polymerase chain reaction using-sequence specific primers (PCR-SSP) was used to amplify exons 2, 3, 4, 5, 6, 7, 9 and 10 of RHD gene and exons 1, 2 and 5 of RHCE gene, as well as intron 4 in each of them.</p><p><b>RESULTS</b>The 131 cases of RhD-negative phenotypes consisted of 60 ccee, 58 Ccee, 5 ccEe, 5 CcEe and 3 CCee. Among them, 83 with the Rh ccee or ccEe phenotypes (63.4%) lacked the eight RHD exons indicated above, while 26 cases with the Rh Ccee, CCee, CcEe phenotypes (19.9%) had all the RHD exons examined. Twenty-two individuals with the Ccee, CCee, CcEe phenotypes (16.8%) carried at least one RHD exon. The phenotypes of the RhD negative individuals carrying the RHD gene were Rh CC or Cc, but not cc.</p><p><b>CONCLUSIONS</b>Three classes of RhD-negative polymorphisms among a population of Han Chinese were observed. Antigen association analysis suggested the existence of a novel class of RhD-negative associated haplotype in Han Chinese. This haplotype consisted of a normal RHCE allele and a nonfunctional RHD gene. It may be beneficial to redefine the RhD-negative blood group among Chinese populations upon clarification of the mechanisms of RHD gene expression and RhD antigen immunization.</p>
Subject(s)
Humans , Asian People , China , Ethnicity , Genetics , Phenotype , Polymerase Chain Reaction , Polymorphism, Genetic , Rh-Hr Blood-Group System , GeneticsABSTRACT
Objective To study the effect and mechanism of antisense oligodeoxynucleotides (ASONs) inhibiting hepatitis B virus (HBV) expression. Methods We designed and synthesized antisense oligodeoxynucleotides directly against HBV PreS 2 gene and noncomplementary sequence control. 2.2.15 cells were chosen as cell model. Inhibitory effect of ASONs on HBV gene expression were assayed by ELISA. Cell apoptosis and proliferation were detected by Fascan Flow Cell Cytometer. Effect of ASONs on cell metabolism was detected by radioimmunoassay (RIA) and MTT assay. Results ASONs were able to effectively inhibit HBV expression. Their inhibitory rates of HBsAg and HBeAg were 66% and 91%, respectively. Noncomplementary sequence control group (both inhibitory rates were 11%) was not able to inhibit HBV expression. ASON might induce host cell apoptosis. Cell apoptosis rates on 3rd and 6th day were 6.10% and 6.43%, respectively. Proliferation index were 37% and 36%, respectively. Results of RIA and MTT showed that ASON had not cytoxicity on host cell. Conclusions Not only are ASON able to inhibit HBV gene expression with sequence specific but also clear HBV in the way of apoptosis.