The Rh blood group system,especially the D antigen,is crucial in transfusion medicine and obstetrics.Weak D phenotypes,caused by mutations in the Rhesus D antigen(RhD)blood group(RHD)gene,result in reduced antigen exp...The Rh blood group system,especially the D antigen,is crucial in transfusion medicine and obstetrics.Weak D phenotypes,caused by mutations in the Rhesus D antigen(RhD)blood group(RHD)gene,result in reduced antigen expression,posing challenges in serological testing and clinical management.Variability in detection methods leads to inconsistent results,making accurate classification difficult.Molecular techniques like polymerase chain reaction and DNA sequencing have significantly improved the identification of weak D variants,offering more reliable transfusion strategies and reducing the risk of alloimmunization.However,challenges such as lack of standardized protocols,cost constraints,and population-specific variations remain.In obstetrics,proper management of pregnant women with weak D is essential to prevent hemolytic disease of the fetus and newborn.Non-invasive prenatal testing using cell-free fetal DNA shows promise in predicting RhD incompatibility and minimizing unnecessary Rh immune globulin administration.Future advancements in highthroughput genotyping and discovery of novel RHD alleles could enhance RhD testing accuracy and efficiency.Standardizing RHD genotyping and adopting genotype-based management strategies for Rh immune globulin therapy and red blood cell transfusions will improve patient safety and clinical outcomes.This review examines the molecular basis,challenges,and future prospects in weak D phenotype management.展开更多
Background Rh blood group system is the most complex and immunogenetic blood group system. Prevalent RHD alleles varied in different populations. The purpose of this study is to determine the molecular basis of weak D...Background Rh blood group system is the most complex and immunogenetic blood group system. Prevalent RHD alleles varied in different populations. The purpose of this study is to determine the molecular basis of weak D and DEL phenotype in Anhui Chinese Han population. Methods The D antigen was determined with IgM monoclonal anti-D conformed to the guidelines for donor testing in China. Weak D samples were identified by an indirect antiglobulin test. DEL phenotype was determined by adsorption and elution test. All the RHD 10 exons were screened by PCR with sequence-specific priming or sequenced for the first-time donors who typed weak D, DEL or D negative by serologic test. Results Of all the 30 799 blood donors, 155 blood samples were found D negative with IgM anti-D; 34 blood samples were found D positive by indirect antiglobulin test or absorption elution test. RHD alleles were identified by nucleotide sequencing. Total 4 RHD alleles were found including two new. One hundred and twenty of 155 （77.4%） of the serologically D negative samples lacked the RHD gene. One D negative was RHD（615de12）. Thirty-two of 155 （20.6%） carried RHD（K409K） among them one carrying 1227G〉A and 845G〉A. Two of 155 （1.3%） was weak D type 15. Conclusions In this study at the molecular level, all DEL phenotype is RHD（K409K）; weak D type 15 is the prevalent weak D allele in Anhui Chinese Han population. Additionally, an improved more efficient method was adopted to amplify all the RHD exons in one PCR program. Our study added to the understanding of molecular mechanisms underlying D antigen expression in Anhui Han population and provided useful information for adopting suitable genotyping strategies in routine use.展开更多
Assume that D is a nuclear space and D'its strong topological dual space.Let{B_t}t∈(0,∞)be a Wiener D'-process.In this paper,the real-valued and D'-valued weak stochastic integral with respect to{B_t}are...Assume that D is a nuclear space and D'its strong topological dual space.Let{B_t}t∈(0,∞)be a Wiener D'-process.In this paper,the real-valued and D'-valued weak stochastic integral with respect to{B_t}are established.AMS Subject Classification.60H05.展开更多
文摘The Rh blood group system,especially the D antigen,is crucial in transfusion medicine and obstetrics.Weak D phenotypes,caused by mutations in the Rhesus D antigen(RhD)blood group(RHD)gene,result in reduced antigen expression,posing challenges in serological testing and clinical management.Variability in detection methods leads to inconsistent results,making accurate classification difficult.Molecular techniques like polymerase chain reaction and DNA sequencing have significantly improved the identification of weak D variants,offering more reliable transfusion strategies and reducing the risk of alloimmunization.However,challenges such as lack of standardized protocols,cost constraints,and population-specific variations remain.In obstetrics,proper management of pregnant women with weak D is essential to prevent hemolytic disease of the fetus and newborn.Non-invasive prenatal testing using cell-free fetal DNA shows promise in predicting RhD incompatibility and minimizing unnecessary Rh immune globulin administration.Future advancements in highthroughput genotyping and discovery of novel RHD alleles could enhance RhD testing accuracy and efficiency.Standardizing RHD genotyping and adopting genotype-based management strategies for Rh immune globulin therapy and red blood cell transfusions will improve patient safety and clinical outcomes.This review examines the molecular basis,challenges,and future prospects in weak D phenotype management.
文摘Background Rh blood group system is the most complex and immunogenetic blood group system. Prevalent RHD alleles varied in different populations. The purpose of this study is to determine the molecular basis of weak D and DEL phenotype in Anhui Chinese Han population. Methods The D antigen was determined with IgM monoclonal anti-D conformed to the guidelines for donor testing in China. Weak D samples were identified by an indirect antiglobulin test. DEL phenotype was determined by adsorption and elution test. All the RHD 10 exons were screened by PCR with sequence-specific priming or sequenced for the first-time donors who typed weak D, DEL or D negative by serologic test. Results Of all the 30 799 blood donors, 155 blood samples were found D negative with IgM anti-D; 34 blood samples were found D positive by indirect antiglobulin test or absorption elution test. RHD alleles were identified by nucleotide sequencing. Total 4 RHD alleles were found including two new. One hundred and twenty of 155 （77.4%） of the serologically D negative samples lacked the RHD gene. One D negative was RHD（615de12）. Thirty-two of 155 （20.6%） carried RHD（K409K） among them one carrying 1227G〉A and 845G〉A. Two of 155 （1.3%） was weak D type 15. Conclusions In this study at the molecular level, all DEL phenotype is RHD（K409K）; weak D type 15 is the prevalent weak D allele in Anhui Chinese Han population. Additionally, an improved more efficient method was adopted to amplify all the RHD exons in one PCR program. Our study added to the understanding of molecular mechanisms underlying D antigen expression in Anhui Han population and provided useful information for adopting suitable genotyping strategies in routine use.
文摘Assume that D is a nuclear space and D'its strong topological dual space.Let{B_t}t∈(0,∞)be a Wiener D'-process.In this paper,the real-valued and D'-valued weak stochastic integral with respect to{B_t}are established.AMS Subject Classification.60H05.
