Molecular characterization of three novel weak D type alleles with additional haplotype data on weak D Types 1.2 and 18

Anani, Waseem Q.; Yassai, Maryam; Bensing, Kathleen M.; Denomme, Gregory A.

doi:10.1111/trf.14045

Cited by 2 publications

(6 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This phenotype had been previously reported in a single study that described a case of a donor identified by molecular biology, after being typed 17 times in previous donations as D-. 20 The presence of this phenotype in our donors shows a founding and restricted effect in this southern region of Brazil.…”

Section: Discussionmentioning

confidence: 60%

Identification of rare blood types in southern Brazil: impact on transfusion support

et al. 2020

View full text Add to dashboard Cite

The prevalence of blood group antigens and phenotypes varies significantly in Brazil. To ensure a proper rare blood supply, it is essential to establish a local and regional database of rare donors connected to the national registry. The objective of this study was to create a database of rare blood donors in the northern region of southern Brazil. From November 2011 to December 2018, red blood cell (RBC) phenotyping and genotyping were performed on common and high-prevalence antigens in donors and patients in southern Brazil. During this study period, 17 patients and 33 blood donors with rare phenotypes were identified. Six patients had already been alloimmunized to clinically significant antigens. Patients with the following phenotypes (i.e., negative for high-prevalence antigens) were found: Yt(a–), Jk(a–b–), Lu(a–b–), Oh (Bombay), Tc(a–), k–, and Fy(a–b–). Among the donors, Kp(a+b–), Fy(a–b–), Lu(a–b–), and k– phenotypes were identified. We also found four donors with the weak D type 18 phenotype. In conclusion, we observed that the prevalence of rare blood phenotypes in our region corresponds more to the prevalence found in the Caucasian population when compared with other regions in Brazil. Our results show the importance of continuous screening for rare donors in different regions of the country and the creation of a local database to support RBC transfusions in patients who need rare blood.

show abstract

Section: Discussionmentioning

confidence: 60%

Identification of rare blood types in southern Brazil: impact on transfusion support

et al. 2020

View full text Add to dashboard Cite

show abstract

“…The observation of a mixed‐field reactivity in some weak D samples 31–36 is interesting and has not been satisfactorily explained to date. The weak D type 18 (p.R7W) demonstrated a flow cytometric readout that can be arbitrarily split in two populations of 195 and 2582 D antigens/red cell, respectively (Figure 1), indicating mixed‐field reactivity.…”

Section: Discussionmentioning

confidence: 98%

“…The remarkably high D antigen density of the DIVa phenotype 62,86 has been proposed to be due to the presence of p.N152T substitution facilitating the integration of RhD protein into the red cell membrane. 62 The observation of a mixed-field reactivity in some weak D samples [31][32][33][34][35][36] is interesting and has not been satisfactorily explained to date. The weak D type 18 (p.R7W) demonstrated a flow cytometric readout that can be arbitrarily split in two populations of 195 and 2582 D antigens/red cell, respectively (Figure 1), indicating mixedfield reactivity.…”

Section: Discussionmentioning

confidence: 99%

“…The mixed-field reactivity, seemingly confirmed by agglutination in gel matrix tests (Figure S1), had not been reported in any of the previous observations of weak D type 18. [32][33][34] The red cells belonged to a pregnant woman and factors other than the RHD variant could have caused the mixed-field reactivity, such as hematologic pathologies and treatment 40 or pregnancy. 84 However, the woman was reported healthy without transfusion.…”

Section: Discussionmentioning

confidence: 99%

“…Of note, molecularly similar variants can have widely variable effects, ranging from no effect (normal D antigen) over weak D and DEL to D-negative, as recently exemplified by RHD breakpoint analysis. 30 Some weak D types, such as type 10 (W393R), 31 type 18 (R7W), [32][33][34] and type 31 (P6L), 35,36 are known to present with irregular quantitative expression of the D antigen, such as mixed-field agglutination during serologic testing or as multiple red cell populations on flow-cytometric histograms. This phenomenon of mixed-field reactivity in blood group antigens has been explained over the years by several mechanisms including transcriptional noise, 37 red cell chimerism, 38,39 maternal-fetal hemorrhage, 40 or sample preparation error during flow cytometry.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Rh flow cytometry: An updated methodology for D antigen density applied to weak D types 164 and 165

Hutchison,

Srivastava,

Polin

et al. 2023

Transfusion

View full text Add to dashboard Cite

BackgroundAn original methodology for determining the D antigen density on red cells was published in 2000 and has been applied in many publications since. This flow cytometry‐based assay remained largely unrevised utilizing monoclonal anti‐Ds that are not readily available anymore. We updated the methodology to quantify erythrocyte D antigen sites using microspheres and monoclonal anti‐Ds that are commercially available today.MethodsThe absolute D antigen density of a frozen standard CcDEe cell, drawn in 2003, a fresh blood donation from the same individual, drawn in 2022, and an internal control CcDEe cell, was quantified by flow cytometry using fluorescence‐labeled microspheres. The internal control CcDEe cell was used in conjunction with 9 commercial anti‐Ds to determine D antigen densities of 7 normal D, 4 partial D, and 11 weak D type samples, including 2 novel alleles.ResultsThe reproducibility of the updated assay was evaluated with red cells of published D antigen densities. The current results matched the known ones closely. The new weak D types 164 and 165 carried 4500 and 1505 D antigens/red cell, respectively. The absolute D antigen density decreased from 27,231 to 26,037 in an individual over 19 years.DiscussionThe updated assay gave highly reproducible results for the D antigen densities of Rh phenotypes. Readily available anti‐Ds allowed for the determination of the D antigen densities of 7 weak D types. The assay is suitable to evaluate the effects of distinct amino acid substitutions on the RhD phenotype.

show abstract

Molecular characterization of three novel weak D type alleles with additional haplotype data on weak D Types 1.2 and 18

Cited by 2 publications

References 6 publications

Identification of rare blood types in southern Brazil: impact on transfusion support

Identification of rare blood types in southern Brazil: impact on transfusion support

Rh flow cytometry: An updated methodology for D antigen density applied to weak D types 164 and 165

Contact Info

Product

Resources

About