| BACKGROUND：The Rhesus (Rh) system is the most complex and immunogenic of the bloodgroup systems. It comprises50antigens corroborated RH1to RH57by the International Society of BloodTransfusion, but only five (D, C, E, c and e) are the most routinely identified due to their unique relation tohemolytic disease of the newborn (HDN) and transfusion reactions. The successful prevention of RhDimmunogenic disease has brought attention to other red blood cells antigens causing alloimmunizationincluding RhC/c and RhE/e. RH genotyping assays are mainly based on research in whites. These assaysmay not be reliable in a multiracial society because of the genetic variation in RH among ethnic groups.Frequency of the Rh alleles shows variation, more than170weak or partial RHD alleles are currentlyknown. A similar heterogeneity of RHCE alleles may be anticipated. Similar to weak D with respect toimmunization are expected to be the same for D and as weak D, partial CE can get immunized against thenormal protein. but a large-scale systematic analysis of the molecular bases of altered C, c,E and eantigenicity blood donors was lacking in China.OBJECTIVES:The purpose of the study was to document the RHCE alleles frequencies and toinferred Rhesus haplotype frequencies by the observation of phenotypes from blood donnors. Analyzecircumstances where defined genotype does not correlate with serological phenotype.Study the molecularbackground of variant RhCE antigens by the leading RHCE variants alleles investigated by molecularbiology. RHCE genetics charateristics and genic structures were analyzed regarding the blood transfusionand obstetrical settings services in China.STUDY DESIGN AND METHODS: RhD negative data of356,071blood donors who madesuccessful whole blood donation(s) between January2005and December2011were reviewed, of these, asubset of10,373random RhD positive WB donors who donated between2010and2011were furtherstudied for RhCE serologically typed using the Xantus200analyzer with two sets of monoclonal anti-C,-c,-E, and-e reagents. Goodness-of-fit statistics were calculated for the figures observed compared to valuesexpected using the Hardy-Weinberg equilibrium. RH allele frequencies and haplotype frequencies werederived by the square-root method. Heterogeneity tests between types were calculated using the chi-squaretest. The multiplex polymerase chain reaction with sequence-specific priming (PCR-SSP) method wasestablished for rapid RHCE genotyping testing. A multiplex PCR-SSP screening for23RHCE alleles wasregistered of the DNA bank GerBS. RHCE variants alleles detected after genotype does not reflect orweakening (obviously diminished reactivity and very weak but no doubt that antigen is present, weak+to+)serologic reaction patterns of the C, c, E, or e antigens in serologic testing. Further analysis of the specificRHCE variants alleles were identified after sequence analysis of genomic DNA. RESULTS: The frequency of Rhesus haplotype were: D：0.9329， d:0.0671,DCe:0.6153,DcE:0.2704,Dce:0.0341,DCE:0.0132,dCe:0.0123,dCE:0.0006,dcE:0.0024,dce:0.0518.There isno statistically significant difference of Rh haplotype frequencies distribution and proportion from Hanethnic groups in China under the Hardy Weinberg law(P>0.05), Overall frequencies of RHCE alleles andhaplotype belonging to the different various RhD blood groups also varied significantly (P<0.05) over theperiod of the study.229samples were surveyed for weakened serologic reaction patterns of the C, c, E, or eantigens in automated testing.54samples genotype does not always reflect phenotype. Altogether22RHCE alleles with distinct single nucleotide substitutions were detected in283samples. RHce（R114W）,RHcE（EI,Ew;M167K）,RHCe (M267K),RHce (VS;L245V) and RHces（G336C）were themost frequent allele，the Dce,dce, DCe and DcE were the most frequent probable variant haplotype.Thevariant RHCE alleles can weaken/lack expression of C, c, E, and e antigens, variant RHCE alleles werepresent in heterozygosity with another common RHCE allele in most cases.CONCLUSION:(1)Rh haplotype frequencies distribution from Han ethnic groups in Chinaunder the Hardy-Weinberg law;(2)We observed a serologic diversity related to the RhC/E phenotype forrare weak RhD typing;(3)Molecular typing can detect the antigens expressed by variant alleles that arecurrently missed by serologic methods in blood donors;(4) The molecular basic of some partial and/orweaked C、c、E、e antigens were characterized, ces340、ceMO and JAL+phenotypes were first reportedin chinese population... |
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