Rh, Kell, Duffy, Kidd and Diego blood group system polymorphism in Brazilian Japanese descendants

Genetic profile of RHCE, Kell, Duffy, Kidd, Diego and MNS hybrid glycophorins blood groups in ethnic northeastern Thais: Alleles, genotypes and risk of alloimmunisation

BACKGROUND

Antibodies against blood group antigens play a key role in the pathophysiology of haemolytic transfusion reactions (HTRs) and haemolytic disease of the fetus and newborn (HDFN). This study aimed to determine the frequencies of alleles, genotypes, and risk of alloimmunisation of clinically significant blood group systems in ethnic northeastern Thais.

METHODS

In total, 345 unrelated, healthy, ethnic northeastern Thais were tested using the in-house PCR-sequence specific primers (PCR-SSP) method for simultaneously genotyping of RHCE, Kell, Duffy, Kidd, Diego and MNS glycophorin hybrids and results confirmed by Sanger sequencing.

RESULTS

In this cohort, the alleles RHCE*C (81.0%) and RHCE*e (84.8%) were more prevalent than RHCE*c (19.0%) and RHCE*E (15.2%). The most common predicted haplotype combinations of the RHCE alleles were C+c-E-e+(R1R1) (59.4%) followed by the C+c+E+e+ (R1R2) (20.6%) and C+c+E-e+ (R1r) (11.3%). The KEL*01 allele was not found in this study. The frequencies of FY*01 and FY*02 were 88.3% and 11.7%, respectively. The genotype FY*02/02 was found in four samples (1.2%). The frequencies of JK*01 and JK*02 were 52.5% and 47.5%, respectively. Homozygous JK*02/02 was found in 81 samples (23.5%). The frequencies of DI*01 and DI*02 were 0.6% and 99.4%, respectively. In total, 64 samples (18.6%) were found to carry the MNS glycophorin hybrids.

CONCLUSIONS

Our results indicated a possible high risk of c, E, Fyb, Jka, Jkb and Mia alloimmunisation in these populations. Moreover, methods established for genotyping clinically significant blood groups in this study can now be utilised in routine clinical application.

Frequency of the DI*A, DI*B and Band 3 Memphis polymorphism among distinct groups in Brazil

INTRODUCTION

The Band 3 is a red blood cell protein that carries the Dia and Dib antigens from the Diego blood system. The SLC4A1 gene encodes Band 3; Band 3 Memphis is a polymorphism of normal Band 3 and has two variants, but only the variant II carries the Dia antigen.

OBJECTIVES

Describe the frequencies of the DI*A and DI*B alleles and the Band 3 Memphis among blood donors, sickle cell disease (SCD) patients and Amazonian Indians.

METHODS

A total of 427 blood samples were collected and separated into three groups: 206 unrelated blood donors, 90 patients with SCD and 131 Amazonian Indians. We performed DI*A/B, normal Band 3 and Band 3 Memphis genotyping, using the Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP).

RESULTS

The frequency of the DI*A/DI*A genotype was 0.5% in blood donors and it was not found in other groups. The frequency of the DI*A/DI*B was higher in Amazonian Indians (33.6%) and the frequency of the DI*B/DI*B was highest in blood donors (92.2%). All 105 individuals tested were positive for the presence of normal Band 3 and of these individuals, only 5/105 (4.8%) presented the Band 3 Memphis mutation.

CONCLUSION

We observed a higher frequency of the DI*B allele in blood donors and a low frequency of the DI*A/DI*A genotype in all groups studied. The Band 3 Memphis was found in a higher frequency in the blood donor group. Our findings highlight the importance of analyzing different population groups to gain a better understanding of the genetic association of blood group antigens.

Frequencies of genetic variants of the Rh, Kell, Duffy, Kidd, MNS and Diego systems of northwest Rio Grande do Sul, Brazil

INTRODUCTION

To date, 340 antigen-organized 43 blood group systems are recognized, being ABO, Rh, Kell, Duffy, Kidd, MNS and Diego the most clinically relevant. The aim of this study was to assess the distribution of alleles and genotypes of the blood group systems Rh, Kell, Duffy, Kidd, MNS and Diego in 810 blood donors registered in the hemotherapy unit in northwest Rio Grande do Sul, Brazil METHODS: We evaluated the genetic variability of blood groups Rh (c.676G>C and c.307C>T), Kell (c.578C>T), Kidd (c.838A>G), Duffy (c.125A>G and c.1-67T>C), Diego (c.2561C>T) and MNS (c.143T>C) in 810 volunteer blood donors of Rio Grande do Sul, southern Brazil. The genetic profiling was performed through allelic discrimination assays using hydrolysis probes (TaqMan®) real-time PCR system.

RESULTS

The most frequent blood group genotypes found in our study population were: RHC*Cc (51.5%), RHC*ee (70.1%), FY*A/FY*B (49.3%), GATA -67T/T (93.5%), KEL*2/KEL*2 (93.4%), JK*A/JK*B (53.2%) and DI*02/DI*02 (95.4%). Some statistical differences were observed on comparing the population of this study with populations from other states in Brazil, mainly with population of Minas Gerais, Bahia and Paraná, which showed some differences from the population of Porto Alegre, which was more similar to those of Santa Catarina and São Paulo CONCLUSION: The frequency of red blood cell polymorphisms in our study is different from that of blood donors in other regions of Brazil. The results showed the importance of extended genotyping in adequate blood screening and the existence of rare genotypes in Brazilian regular blood donors.

Genotyping for Dombrock blood group alleles in Northern Pakistani blood donors

Genotyping can be used to identify rare blood group antigens and to solve suspected blood group discrepancies, particularly when serologic methods are limited. Unfortunately, only a few such studies have been performed in Pakistan. The present study was conducted to determine the frequency of Dombrock blood group alleles by genotyping samples from blood donors from the north of Pakistan. Blood samples were taken with consent from 300 blood donors; DNA was extracted and tested for DO*01 and DO*02 alleles by sequence-specific primer polymerase chain reaction (PCR-SSP), followed by gel electrophoresis. Allele frequencies were calculated. The observed and expected genotype frequencies were compared using the χ² test. The allele frequencies for DO*01 and DO*02 were 0.40 and 0.60, respectively. Genotype frequencies were in Hardy-Weinberg equilibrium. This study in Pakistani blood donors provides Dombrock blood group allele frequencies by PCR-SSP. This approach is efficient and economical and can be applied in developing countries. The findings can contribute to the development of in-house red blood cell panels, identification of rare blood types, and establishment of a national rare blood donor program.

Genotyping can be used to identify rare blood group antigens and to solve suspected blood group discrepancies, particularly when serologic methods are limited. Unfortunately, only a few such studies have been performed in Pakistan. The present study was conducted to determine the frequency of Dombrock blood group alleles by genotyping samples from blood donors from the north of Pakistan. Blood samples were taken with consent from 300 blood donors; DNA was extracted and tested for DO*01 and DO*02 alleles by sequence-specific primer polymerase chain reaction (PCR-SSP), followed by gel electrophoresis. Allele frequencies were calculated. The observed and expected genotype frequencies were compared using the χ² test. The allele frequencies for DO*01 and DO*02 were 0.40 and 0.60, respectively. Genotype frequencies were in Hardy-Weinberg equilibrium. This study in Pakistani blood donors provides Dombrock blood group allele frequencies by PCR-SSP. This approach is efficient and economical and can be applied in developing countries. The findings can contribute to the development of in-house red blood cell panels, identification of rare blood types, and establishment of a national rare blood donor program.

Blood groups in Native Americans: a look beyond ABO and Rh

The study presents comparisons between blood group frequencies beyond ABO and Rh blood systems in Native American populations and previously published data from Brazilian blood donors. The frequencies of Diego (c.2561C>T, rs2285644), Kell (c.578C>T, rs8176058), Duffy (c.125A>G, rs12075, c.1-67T>C, rs2814778) and Kidd (c.838A>G, rs1058396) variants in Kaingang (n=72) and Guarani (n=234) populations from Brazil (1990-2000) were obtained and compared with data from these populations sampled during the 1960s and with individuals of different Brazilian regions. Data showed high frequencies of DI*01 and FY*01 alleles: 11.8% and 57.6% in Kaingang and 6.8% and 75.7% in Guarani groups, respectively. The main results indicated: (1) reduction in genetic distance over time of Kaingang and Guarani in relation to other Brazilian populations is suggestive of ongoing admixture; (2) significant differences in some frequencies of blood group markers (especially Diego, Kidd and Duffy) in relation to Native Americans and individuals from different geographical regions of Brazil. Our study shows that the frequency of red blood cell polymorphisms in two Native American groups is very different from that of blood donors, when we evaluated blood groups different from ABO and Rh systems, suggesting that a better ethnic characterization of blood unit receptors is necessary.

Frequency of antigen Dia on the blood donor population of the Hemocenter coordinator of the Hemopa Foundation

Introduction

Erythrocyte phenotyping is a very important test in the adoption of prophylactic measures to reduce transfusion reactions/alloimmunizations in polytransfused patients. The blood group Diego, in its current, form has 22 antigens, of which 4 are immunogenic, being Diª/Di^b and W^ra/W^rb, while the others are less expressive. The antigen Diª is of low incidence among whites and blacks, however, it is common in the South American indigenous and Asian Mongolian populations. It is also considered a system of clinical importance for its immunogenicity.

Method

The present study aimed to carry out a retrospective and descriptive survey of the frequency of the Diª antigen in the blood donor population at the HEMOPA Foundation Coordinating Blood Center from 12/2018 to 1/2000. The data obtained were from the HEMOPA Foundation SBS Progress and SBS WEB Systems databases.

Results

During this period, 941,744 blood bags were collected and, of these, 930 bags were phenotyped for the Diª antigen, of which 842 were negative and 88 (9.7%) positive. The research showed that, among the positive donors for the antigen Diª, 88.6% were brown, 3.4%, black and 8%, white. In the statistical analysis, the frequency observed was higher in browns.

Conclusion

In the present investigation, we concluded that our region has a relatively higher frequency of the Diª antigen, when compared to the rest of Brazil, and it occurs more often in browns.

Using droplet digital PCR to screen for rare blood donors: Proof of principle

BACKGROUND

Digital droplet PCR (ddPCR) is a very sensitive high throughput genotyping methodology. To date, the use of ddPCR in immunohematology is restricted to fetal genotyping of red blood cell antigens. Our hypothesis is that this technology could be applied to screen for rare red blood cell genotypes, such as Di(b-).

METHODS

Nucleic acid of 3168 donors was extracted for viral screening routine in pools of 6, which were converted into three types of 48-donor pools: control pools (only DI*B/*B samples), pools with varying amount of DI*A/*B samples (n = 1-5) and a pool with one rare DI*A/*A sample. Pools were genotyped using ddPCR to detect and quantify DI*A and DI*B alleles.

RESULTS

DI*A allele was accurately detected in all pools containing Di(a + b+) samples and in the pool containing one Di(a + b-) sample. No copies were detected in the control pools (n = 60). The ratio between the number of DI*A and DI*B copies varied significantly between the pools and the triplicates.

CONCLUSION

The proposed ddPCR assay was accurate in identifying the rare DI*A allele in large pools of donors and can be applied to screen for Di(b-) phenotype. The strategy can potentially be extended to search for other rare RBC phenotypes.

Genetic variability of blood groups in southern Brazil

We evaluated genetic variability among the blood groups Kell (c.578C > T and c.1790T > C), Kidd (c.838A > G), Duffy (c.125A > G, c.265C > T and c.1-67T > C), Diego (c.2561C > T), MNS (c.143T > C) and Rh (c.676G > C) in Rio Grande do Sul in southern Brazil. Genetic profiling from 382 volunteer blood donors was performed through allelic discrimination assays using a hydrolysis probe (TaqMan®) with a real-time PCR system. The sample was divided into two groups: Euro-Brazilian and Afro-Brazilian. A comparison with studies from other regions of Brazil and the 1000 Genomes Database showed significant differences for almost all polymorphisms evaluated in our population. Population differentiation between the Euro- and Afro-Brazilian groups was low (F_ST value 0.055). However, when each locus was evaluated individually, KEL*06 and FY*02N.01 allele frequencies were significantly higher in the Afro-Brazilian group than in the Euro-Brazilian group. Ethnic classification that uses phenotypic criteria to find blood units with rare antigens may be important when there is a need to detect blood units with an absence of Duffy antigens. There is also a greater probability of finding donors in the Afro-Brazilian group. Taken together, the data indicate strong European and African contributions to the gene pool, with intense admixture.

The Necessity of Clinical Rh Phenotypic Serological Detection and Homotypic Infusion in Patients with Repeated Blood Transfusion

Background

This study analyzed the distribution of Rh serological phenotype in people living in Hangzhou, China, and assessed the necessity of its routine clinical detection and homotypic infusion.

Material/Methods

Blood donors and patients who might need blood transfusion were enrolled into the study, and ABO and 5 major Rh serological antigens (C, c, D, E, and e) were routinely detected. The consistent ABO and Rh serological phenotype blood was transfused between the blood donors and recipients. Irregular antibodies were screened and identified in patients before the blood transfusion. Then, the transfusion adverse effects were monitored and compared with the previous data in the hospital.

Results

The phenotypic frequencies of Rh blood groups were D>C>E>c>e. The CCDee was the most common phenotype and CcdEe was the least common. The detection rate of unexpected antibodies gradually increased, while the unexpected antibodies slowly decreased in the Rh system. There was a correlation between the isotypic infusion of 5 Rh antigens and the detection rate of antibodies in the Rh system (R=0.845). The adverse effects of blood transfusion declined from 19.95% in 2011 with just homotypic ABO infusion to 3.098% in 2019 with the transfusion of homotypic ABO and the 5 major Rh serological antigens.

Conclusions

The consistency of the transfusion with ABO and 5 significant Rh serological antigens could prevent and decrease the high frequency production of isoantibodies, which is of vital importance in reducing the incidence rate of adverse effects in patients receiving transfusions.

DI*A and DI*B Allele Frequencies Among Southern Thai Blood Donors

Diego (DI) blood group genotyping is clinically important in Asian populations. Data of Diego blood type among southern Thais is still unknown. This study aimed to report DI*A and DI*B allele frequencies in southern Thai blood donors and to estimate potential risk of Di^a incompatibility and alloimmunization in Thai populations. DNA samples obtained from 427 southern Thai blood donors were genotyped for DI*A and DI*B alleles by polymerase chain reaction with sequence-specific primer. DI*A and DI*B allele frequencies among southern Thais were 0.0047 and 0.9953. Their frequencies were similar to those among American Native, Italian, Filipino, Alaska Native/Aleut and Hawaiian/Pacific Islander populations; while, the frequencies significantly differed from central and northern Thai, Southeast Asian, Brazilian, Southern Brazilian, Brazilian Japanese descendants, Japanese, Han Chinese, Chinese, and Korean populations (P < 0.05). The Di^a incompatibility among southern Thais (0.93%) was lower than among central Thais (3.49%), corresponding to a significantly lower probability of Di^a alloimmunization (P < 0.05). This is the first report of DI*A and DI*B allele frequencies among southern Thais, which is beneficial for not only creating information for estimating risk of alloimmunization, but also providing antigen-negative red cell donors to prevent both alloimmunization and adverse transfusion reactions.

Genetic polymorphisms of human platelet antigens in Euro-African and Japanese descendants from Parana, Southern Brazil

The frequency distributions of HPA-1 to HPA-6 and HPA-15 were evaluated in two Brazilian populations from Parana: a mixed population of predominantly Caucasians and a population of Japanese descendants. Genotyping was performed by PCR-SSP in 364 unrelated individuals. Differences in the distribution of HPA highlight diversity in Brazilian miscegenation and the importance of formation of the HPA panel composed of regional blood donors.

Duffy blood group genotyping in Thai blood donors

Background

Duffy (FY) blood group genotyping is important in transfusion medicine because Duffy alloantibodies are associated with delayed hemolytic transfusion reactions and hemolytic disease of the fetus and newborn. In this study, FY allele frequencies in Thai blood donors were determined by in-house PCR with sequence-specific primers (PCR-SSP), and the probability of obtaining compatible blood for alloimmunized patients was assessed.

Methods

Five hundred blood samples from Thai blood donors of the National Blood Centre, Thai Red Cross Society, were included. Only 200 samples were tested with anti-Fy^a and anti-Fy^b using the gel technique. All 500 samples and four samples from a Guinea family with the Fy(a-b-) phenotype were genotyped by using PCR-SSP. Additionally, the probability of obtaining antigen-negative red blood cells (RBCs) for alloimmunized patients was calculated according to the estimated FY allele frequencies.

Results

The FY phenotyping and genotyping results were in 100% concordance. The allele frequencies of FY^*A and FY^*B in 500 central Thais were 0.962 (962/1,000) and 0.038 (38/1,000), respectively. Although the Fy(a-b-) phenotype was not observed in this study, FY^*B^ES/FY^*B^ES was identified by PCR-SSP in the Guinea family and was confirmed by DNA sequencing.

Conclusions

Our results confirm the high frequency of the FY^*A allele in the Thai population, similar to that of Asian populations. At least 500 Thai blood donors are needed to obtain two units of antigen-negative RBCs for the Fy(a-b+) phenotype.

Distribution of DI*A and DI*B Allele Frequencies and Comparisons among Central Thai and Other Populations

Alloantibodies to the Diego (DI) blood group system, anti-Dia and anti-Dib are clinically significant in causing hemolytic transfusion reactions (HTRs) and hemolytic disease of the fetus and newborn (HDFN), especially in Asian populations with Mongolian ancestry. This study aimed to report the frequency of the DI*A and DI*B alleles in a Central Thai population and to compare them with those of other populations previously published. Altogether, 1,011 blood samples from unrelated healthy blood donors at the National Blood Centre, Thai Red Cross Society, Bangkok were included. Only 391 samples were tested with anti-Dia by conventional tube technique. All samples were genotyped for DI*A and DI*B alleles using an in-house polymerase chain reaction with sequence-specific primer (PCR-SSP) technique. The DI phenotyping and genotyping results were in 100% concordance. The DI*A and DI*B allele frequencies among 1,011 Central Thais were 0.0183 (37/2,022) and 0.9817 (1,985/2,022), respectively. Allele frequencies were compared between Central Thai and other populations. Our data shows that DI*A and DI*B allele frequencies are similar to Southeast Asian, Brazilian, Southern Brazilian and American Native populations; whereas, these frequencies significantly differ from those reported in East Asian, Italian, Alaska Native/Aleut, Hawaiian/Pacific Islander and Filipino populations (P<0.05), corresponding to the results of a matrix of geometric genetic distances. This study confirms that the prevalence of DI*A and DI*B alleles among Central Thais is similar to Southeast Asians and different to others populations of the world. A PCR-based identification of DI genotyping should overcome some of the serological limitations in transfusion medicine and provides a complementary tool for further population-genetic studies.

Profile of Rh, Kell, Duffy, Kidd, and Diego blood group systems among blood donors in the Southwest region of the Paraná state, Southern Brazil

The aim of this study was to assess the distribution of alleles and genotypes of the blood group systems Rh, Kell, Duffy, Kidd, and Diego in 251 regular blood donors registered in the hemotherapy unit of the Southwestern region of Paraná, Southern Brazil. The frequencies were obtained by direct counting on a spreadsheet program and statistical analyses were conducted in order to compare them with other Brazilian populations using chi-squared with Yates correction on OpenEpi software. The frequencies of RHD* negative, RHCE*c/c and RHCE*e/e were higher than expected for the Caucasian population. A difference was also observed for FY alleles, FY*01/FY*01 genotype and FY*02N.01 -67T/C (GATA Box mutation). Two homozygous individuals were defined as a low frequency phenotype K + k- (KEL*01.01/KEL*01.01) and, for Diego blood group system the rare DI*01 allele was found in ten blood donors, of which one was DI*01/DI* 01 (0.4%). The allele and genotype frequencies of Kidd blood group system were similar to expected to Caucasians. The results showed the direction in which to choose donors, the importance of extended genotyping in adequate blood screening and the existence of rare genotypes in Brazilian regular blood donors.

Frequencies of red blood cell major blood group antigens and phenotypes in the Chinese Han population from Mainland China

Alloantibodies directed to red blood cell (RBC) antigens play an important role in alloimmune-mediated haemolytic transfusion reactions and haemolytic disease of the foetus and newborn. The frequencies and phenotypes of RBC antigens are different in populations from different geographic areas and races. However, the data on major blood group antigens in the Chinese Han population from Mainland China are still very limited; thus, we aimed to investigate them in this study. A total of 1412 unrelated voluntary Chinese Han blood donors were randomly recruited. All donors were typed for blood group antigens: D, C, c, E, e, C(w) , Jk(a) , Jk(b) ,M, N, S, s, Le(a) , Le(b) , K, k. Kp(a) , Kp(b) , Fy(a) , Fy(b) , Lu(a) , Lu(b) , P1 and Di(a) using serological technology. Calculations of antigen and phenotype frequencies were expressed as percentages and for allele frequencies under the standard assumption of Hardy-Weinberg equilibrium. Amongst the Rh antigens, D was the most common (98.94%) followed by e (92.28%), C (88.81%), c (58.43%), E (50.78%) and C(w) (0.07%) with DCe/DCe (R1 R1 , 40.72%) being the most common phenotype. In the Kell blood group system, k was present in 100% of the donors and a rare phenotype, Kp (a+b+), was found in 0.28% of the donors. For the Kidd and Duffy blood group systems, Jk (a+b+) and Fy (a+b-) were the most common phenotypes (44.05% and 84.35%, respectively). In the MNS blood group system, M+N+S-s+ (45.54%) was the most common, whereas M+N-S-s- and M-N+S-s- were not found. The rare Lu (a-b-) and Lu (a+b+) phenotypes were identified in 0.43% and 1.13% of the donors, respectively. Le(a) and Le(b) were seen in 17.92% and 63.03% of donors, respectively. The frequency of Di(a) was 4.75%, which was higher than in the Chinese population in Taiwan region or the Caucasian and Black populations (P < 0.0001). This study systematically describes the frequencies of 24 blood group antigens in the Chinese Han population from Mainland China. The data can be helpful in creating a donor database for preparation of indigenous cell panels and providing antigen-negative blood to patients with multiple alloantibodies.

Clinical Potential of Effective Noninvasive Exclusion of KEL1-Positive Fetuses in KEL1-Negative Pregnant Women

Background: The clinical importance of assessing the fetal KEL genotype is to exclude ‘K'-positive fetuses (genotype KEL1/KEL2) in ‘K'-alloimmunized pregnant women (genotype KEL2/KEL2). Noninvasive assessment of the fetal KEL genotype is not yet available in the Czech Republic. Objective: The aim of this study was to assess the fetal KEL1/KEL2 genotype from cell-free fetal DNA in the plasma of KEL2/KEL2 pregnant women. Methods: The fetal genotype was assessed by minisequencing (a dilution series including control samples). A total of 138 pregnant women (between the 8th and 23rd gestational week) were tested by minisequencing. The fetal genotype was further verified by analysis of a buccal swab from the newborn. Results: Minisequencing proved to be a reliable method. In 2.2% (3/138) of the examined women, plasma sample testing failed; 94.8% (128/135) had the KEL2/KEL2 genotype, and a total of 3.1% of fetuses (4/128) had the KEL1/KEL2 genotype. Sensitivity and specificity reached 100% (p < 0.0001). Conclusion: Minisequencing is a reliable method for the assessment of the fetal KEL1 allele from the plasma of KEL2/KEL2 pregnant women.