|
 Previous Article | Table of Contents | Next Article 
Blood, Vol. 94 No. 12 (December 15), 1999:
pp. 4337-4342
DAR, a New RhD Variant Involving Exons 4, 5, and 7, Often in
Linkage With ceAR, a New Rhce Variant Frequently Found in
African Blacks
By
M.B. Hemker,
P.C. Ligthart,
L. Berger,
D.J. van Rhenen,
C.E. van
der Schoot, and
P.A. Maaskant-van Wijk
From the Laboratory for Transfusion Science, Bloodbank Rotterdam,
Rotterdam, The Netherlands; the Department of Immunohematology, CLB and
Laboratory for Experimental and Clinical Immunology, Academic Medical
Center, University of Amsterdam, Amsterdam, The Netherlands; the
Department of Hematology, University Hospital Rotterdam, Rotterdam, The
Netherlands; and the Department of Hematology, Academic Medical Center,
Amsterdam, The Netherlands.
 |
ABSTRACT |
The highly polymorphic Rh system is encoded by 2 homologous genes
RHD and RHCE. Gene rearrangements, deletions, or point
mutations may cause partial D and CE antigens. In this study, a new
RHD variant, DAR, and a new RHCE variant,
ceAR, are described in 4 Dutch African Blacks. Serologically,
DAR showed weaker reactions with a monoclonal antibody and polyclonal
antiserum against D. The DAR phenotype was characterized by complete
loss of at least 9 of 37 Rh D epitopes. Erythrocytes expressing ceAR
were all typed as VS , V+. DNA analysis
showed a partial D allele with only 3 mutations: C602G (exon 4), T667G
(exon 5), and T1025C (exon 7). The ceAR allele carried G48C (exon 1), a
hybrid exon 5 (A712G, C733G, A787G, and T800A), and A916G (exon 6). To
study the frequency of these variants, 326 South-African Blacks was
screened genomically. Of the 326 donors, 16 (4.9%) carried the DAR
allele, 20 (6.1%) the ceAR allele, and 14 (4.3%) both mutated
alleles. Five of these donors (1.5%) had the DAR phenotype, indicating
that they carried the DAR allele homozygously or next to a D-negative
allele. Immunogenicity of the D antigen for individuals with the DAR
phenotype was proven, because 1 of the 4 Dutch individuals produced
allo-antibodies against D after multiple transfusions with D-positive
blood. In a multiethnic society, the prevalence of this D phenotype
will increase and is therefore relevant in transfusion practice and in
prevention of hemolytic disease of the newborn.
© 1999 by The American Society of Hematology.
| |
INTRODUCTION |
THE RHESUS (Rh) BLOOD-GROUP system is
clinically important, because antibodies against Rh antigens are
involved in hemolytic disease of the newborn, hemolytic transfusion
reactions, and autoimmune hemolytic anemia.
The Rh system is complex; as many as 45 different antigens have been
serologically defined.1,2 These antigens are carried by
nonglycosylated, nonphosphorylated polypeptides. The Rh polypeptides are predicted to have 12 transmembrane-spanning domains with
intracellular N- and C-termini, resulting in 6 extracellular loops on
which the Rh antigens are located.3,4 Two highly homologous
genes, RHCE and RHD, encode the Rh antigens. Both genes
are localized on chromosome 1p34.3-p36.1 and are inherited
together.5 RHCE gives rise to the C/c and E/e
polymorphisms. RHD encodes the RhD antigen. Total or partial
deletion of the RHD gene can result in the D-negative
phenotype.6-10 In non-Whites, it has been found that D
negativity can appear in individuals carrying the complete RHD
gene.11,12
The most immunogenic Rh antigen is the Rh D antigen, comprising at
least 30 epitopes.13,14
Partial D phenotypes, characterized by loss of epitopes, can arise from
replacement of RHD exons by their RHCE counterparts, as
has been shown in DIIIb, DIIIc,
DIVb, DVa, DVI, DFR, and DBT and by
point mutations in the RHD gene that occur in DII,
DIVa, DVII, DHMi, DNU, and DHR. Frequencies of
DVII, DVI, DIV, DV,
DII-like, and DFR are 1:900, 1:6,800, 1:10,000, 1:30,000,
1:30,000, and 1:60,000, respectively, as established with serological
methods in a White population.15 Alloantibodies may be
produced against missing epitopes in individuals expressing rhesus D
variants when exposed to the complete antigen by blood transfusion or
during pregnancy.
Three types of RHCE variants have been described.16
Single point mutations are found in VS, V, Cw,
Cx, and Rh:26. RHCE exon replacements, in which
exons of different alleles of RHCE are exchanged, were found in
rGr and a variant in which exon 1 and intron 1 of the
c-allele are replaced by the corresponding part of the C-allele.
Finally, replacement of RHCE exons by their RHD
equivalents may occur, as is found in D , Dc,
RoHar, RN, and partial E. As in
RHD variants, these exon replacements or mutations not only
result in loss of epitopes, but may also account for the formation of
new epitopes.
In the present report, we describe a new partial D antigen, called DAR,
expressed in 4 unrelated Dutch women of African Black origin. In these
4 individuals, a variant RHCE gene, called ceAR, was
also found. That more African Blacks are carrier of the mutated RHD gene was suggested by the fact that 3 of these 4 women were noticed in a routine pregnancy screening. Thereafter, blood was sent
for confirmation of the rhesus typing to the Central Laboratory for
Blood Transfusion (CLB; Amsterdam, The Netherlands). We
also screened 326 African Black donors from the South African Blood Transfusion Service (Johannesburg, South Africa) for DAR and
ceAR.
| |
MATERIALS AND METHODS |
Samples
EDTA anticoagulated blood samples were obtained from 4 unrelated
African Black women (identification numbers 3308, 3424, 3895, and
4413). Three samples were noticed because of weak D expression during
routine pregnancy screening and were sent to the CLB for confirmation.
A blood sample of individual 4413 was referred to our lab because
antibodies were detected. Red blood cells (RBCs) of these individuals
were Rh phenotyped according to standard protocols with monoclonal
antibody (MoAb) MS-201 (CLB) recognizing D epitope 6/7 (9-epitope
model; equal to D-epitope 12 in the 37-epitope model), a polyclonal
reagent (anti-D with bromelain as enhancer; CLB), and MoAbs (all
obtained from CLB) recognizing C (MS 24), c (MS 32), E (MS 260), or e
(MS 21, MS 63). Polyclonal reagents 97-501639 (patient serum) and
Q-sera were used to phenotype VS and V, respectively. The presence of
the low incidence antigen DW, thus far only found in
DVa, was tested with an anti-Rh23 by C. Green and G. Daniels (International Blood Group Reference Laboratory, Bristol, UK).
Phenotyping for partial D was performed with a panel of selected MoAbs
with known epitope specificity (Third International Workshop on
Monoclonal Antibodies against Red Cell and Related Antigens, 1996, Nantes, France).17 RBCs of donor 3424 were sent to the
IBGRL (Bristol, UK) for confirmation.
In the blood sample of individual 4413, erythrocyte antibodies were
present with the specificity of anti-D, -C, -E, -Fya,
-Jka, -M, and -Sla. This individual suffered
from sickle cell anemia and received multiple transfusions over the
years. Adsorption-elution techniques were used to determine whether the
anti-D antibodies were alloantibodies or autoantibodies.
Blood samples of 326 South-African Black donors were randomly collected
by the South African Blood Transfusion Service in Johannesburg
(courtesy of J. Hooydonk, Johannesburg, South Africa). Seven donors
were serologically typed as RhD negative, and all other donors were RhD positive.
cDNA Sequence Analysis
White blood cell-reduced RBCs were enriched with reticulocytes as
described before.18,19 RNA was isolated from the
reticulocyte-enriched fraction.20 cDNA was obtained by
reverse transcriptase-polymerase chain reaction (RT-PCR; using
Superscript II RNAse H-RT; GIBCO BRL, Gaithersburg, MD), and
full-length amplification was performed with consensus primers as
described in Table 1. PCR products were
ligated into pGEM-T vector (system I; Promega, Madison, WI), and the
vectors were introduced into competent Escherichia coli by
electroporation.21 Inserts were cycle-sequenced
automatically (ABI-PRISM 377, DNA sequencer; Perkin-Elmer, Norwalk, CT)
on both strands.
Genomic DNA Analysis
Genomic DNA was isolated from peripheral blood leukocytes with a DNA
isolation kit (Puregene, Minneapolis, MN).
Sequence analysis.
On genomic DNA, exon-specific PCRs were used. All primers are listed in
Table 1. Exons 4 to 5 (including intron 4) and 7 were amplified with
RHD-specific primers (R496/Rex5AD2 and R973/R1068, respectively) and cycle-sequenced automatically (ABI-PRISM 377, DNA
sequencer). Exon 5 and exon 6 were amplified with consensus primers
(Rex5S2/Rex5A and Rex6S/Rex6A, respectively); PCR products were subcloned and sequenced.
PCR assays.
Five PCR allele-specific primer amplifications (ASPAs) were
designed specifically for detection of mutations. Primerset R31/R147 and internal control primer R-15 (all 3 primers located in exon 1) were
used to recognize the C-specific nucleotide at position 48.22 An ASPA specific for CE nucleotides at
position 602 and 667 (primerset R581/R667) was developed to amplify
intron 4. We applied an exon 5 ASPA, using a CE-specific sense
primer (R678) and a D-specific antisense primer
(Rex5AD2), to detect a hybrid exon 5. An exon 5 to 6 ASPA
was used to amplify intron 5 with the CE-specific sense primer
R678 in exon 5 and the D-specific antisense primer R933 in exon
6. An exon 6 to 7 ASPA (primerset R973/R1044) with a D-specific
sense primer in exon 6 and a CE-specific antisense primer in
exon 7 was developed to detect the CE-specific mutation in
D-exon 7.
RHD-specific multiplex PCR.
RHD exons 3, 4, 5, 6, 7, and 9 were amplified with
RHD-sequence specific primers in a 1-reaction mixture assay as
described before.23
Restriction fragment length polymorphism of RH intron 5.
To determine the origin of the intron 5 of the ceAR allele, intron 5 was amplified with sense primer R716 (specific for nt 733G, present in
the CE allele of VS+ individuals and in the D allele) and
antisense primer R870 (consensus primer). This product was
D-specifically digested with restriction enzyme Apa I (New
England Biolabs Inc, Beverly, MA) and analyzed by electrophoresis in a
1% agarose gel.
Southern blot analysis.
Ten micrograms of DNA from all donors was digested with the
endonuclease BamHI and, after electrophoresis, transferred to a
nitrocellulose membrane. Blots were hybridized with a
32P-labeled RH full-length cDNA (kindly provided by
Dr D. Anstee, IBGRL). The results were visualized by autoradiography.
PCR Conditions
All PCR assays were performed in a Perkin-Elmer Cycler Model 480 on 200 ng of cDNA or gDNA in a total volume of 50 µL. Reaction mixtures
contained 50 ng of each primer, 0.2 mmol/L of each dNTP (Pharmacia,
Uppsala, Sweden), and 2 U of Taq DNA polymerase (Promega) in the appropriate buffer supplemented with 1.5 mmol/L
MgCl2.
PCR conditions were 1 cycle of 5 minutes at 95°C, followed by 35 cycles of 1 minute at 95°C, with an annealing time and temperature as described in Table 1 and, depending on the size of the expected product, the extension time at 72°C varied between 45 seconds and
2.5 minutes. Extension was completed during 5 minutes at 72°C.
| |
RESULTS |
Serology
Individuals 3308, 3424, 3895, and 4413 were serologically typed as
C, c+, E, and
e+, VS, and V+. RBCs of
these 4 individuals showed weaker reactions with anti-D MoAb MS-201 and
polyclonal anti-D antiserum than did normal Rh (D)-positive control
cells. Therefore, with restricted screening protocols, these donors
might be considered as expressing weak D. However, extensive
serological studies of all 4 individuals showed a new partial D pattern
(Table 2) in which 9 of the 37 epitopes
were completely missing and 6 of the 37 epitopes showed different
results with several MoAbs. These results were confirmed by Joyce
Poole's laboratory of the IBGRL. RBCs of these 4 donors did not carry
the low incidence anti- gen DW.
View this table:
[in this window]
[in a new window]
|
Table 2.
Epitope Models (9 and 37) With the Reaction Pattern of
the New Partial D Tested With MoAbs Described in the Nantes Workshop
(1996)
|
|
The antibodies present in the serum of patient 4413 were characterized
with the adsorption-elution technique. It was shown that antibodies
directed against D were present, among other antibodies. With
agglutination studies it was shown that these antibodies did not react
with her own erythrocytes or with the erythrocytes of other donors with
the DAR phenotype, but did react with erythrocytes from normal
D-positive donors, indicating that these antibodies are allo-anti-D.
cDNA Sequence Analysis
Sequencing of cDNA from 1 individual (identification no. 3424) showed
the presence of 3 different transcripts
(Fig 1). At least 3 clones per different
transcript were completely sequenced: (1) a normal ce
transcript; (2) a ce-like transcript carrying G48C (Trp16Cys)
in exon 1; A712G (Met238Val), C733G (Leu245Val), A787G (Arg263Gly) and
T800A (Met267Lys) in exon 5; and A916G (Ile306Val) in exon 6; and (3)
a D-like transcript carrying C602G (Thr201Arg) in exon 4, T667G
(Phe223Val) in exon 5, and T1025C (Ile342Thr) in exon 7.
View larger version (20K):
[in this window]
[in a new window]
| Fig 1.
Transcripts as found by sequencing cDNA. Nucleotides
derived from the RHCE sequence are represented by a thin line,
whereas nucleotides derived from the RHD-specific sequence are
represented by a fat line. RHD-specific exons or exon parts are
represented by a gray rectangle, whereas those of RHCE are
given in white.
|
|
Genomic DNA Analysis
To confirm the mutations found in cDNA of individual 3424, as well as
to show the presence of the mutations in the other 3 individuals, 3308, 3895, and 4413, analysis on genomic DNA was performed. All of these
results were in full concordance with the cDNA analysis.
From individual 4413, not only the exons of interest, but also all
exons were amplified from genomic DNA and subsequently cycle-sequenced.
No other mutations were found.
The mutations found in the ce-like transcript were confirmed on
genomic DNA by an ASPA that recognized the C-specific nucleotide at
position 48; by sequence analysis of ce-exon 5 that showed the
mutations A712G, C733G, A787G, and T800A; and by sequence analysis of
ce-exon 6 that showed A916G. The ce origin of intron 5 was indicated by a remaining uncut part, after D-specific digestion with Apa I of the 1,791-bp product, obtained after
D/VS-specific amplification of intron 5.
The mutations found in the D-like transcript were detected by
sequence analysis of RHD-exon 4 to 5 and exon 7. Beside the mutations C602G and T667G, sequence analysis showed a normal
D-intron 424 and the T1025C mutation in D-exon 7. To show that only the mutated D transcript was present, in the absence
of a normal D allele, the RHD-specific multiplex was performed.
The 200-bp internal control fragment from the  -actin gene was
amplified from all 4 DNA samples. Amplification products from exons 3, 6, 7, and 9 were detected, whereas exons 4 and 5 were not amplified.
Southern blot analysis.
The BamHI digestion pattern of the genomic DNA from the 4 individuals (3308, 3424, 3895, and 4413) showed no difference in the Rh
patterns compared with those of a normal D-positive donor.
Screening of the South-African Black Donors
In 56 of the 326 South-African Black donors (17.2%), the RHCE
intron 4 PCR demonstrated the 2 CE-specific nucleotides in the exon 4 and 5 of the RHD gene, with a D intron 4 in between. All 56 of these donors were serologically RhD positive. In 16 of these 56 donors, the presence of T1025C was proven by the D-CE
hybrid exon 6 to 7 PCR, indicating the presence of the DAR allele.
Because a linkage between the DAR and the ceAR allele
was assumed, we tested all 326 donors for the presence of the
ceAR allele. In 20 of the 326 donors (6.1%), the
CE-D hybrid exon 5 PCR and the CE-D
hybrid exon 5 to 6 PCR gave positive results, indicating the presence
of a ceAR allele. Of those 20 donors, 14 were also carriers of
the DAR allele. Thus, 2 donors carried the DAR allele without the ceAR allele and 6 donors carried the ceAR
allele without the DAR allele.
Five of the 14 donors carrying the DAR and ceAR allele
(1.5%) had the deviant RHD multiplex PCR pattern, missing exon 4 and 5. This indicates that these 5 donors were either homozygous for the
DAR or carried DAR on 1 allele and lacked RHD on the other. The results
found on gDNA of these 5 donors were serologically confirmed and gave
with all 5 the same 37-epitope pattern as shown in Table 2.
In DNA of the 40 donors carrying only the C602G and T667G mutations in
exon 4 and 5 of the RHD gene and not the T1025C mutation in
exon 7, the CE-D hybrid exon 5 PCR and the
CE-D hybrid exon 5 to 6 PCR gave negative results,
indicating the absence of the ceAR allele. One of these 40 donors showed the deviant RHD multiplex PCR pattern, missing exons 4 and 5.
| |
DISCUSSION |
In this study, a newly discovered D variant named DAR that occurs
frequently in African Blacks is described. This new D variant consists
of a D allele with 3 point mutations on polymorphic sites, in
which D-specific nucleotides are replaced by
CE-specific ones. These mutations are located in exon 4 (nt
602), exon 5 (nt 667), and exon 7 (nt 1025). The 4 probands also had a
variant ce allele, called ceAR. This allele had a
C-specific mutation on nt 48 in exon 1, a hybrid exon 5 in which the
polymorphic sites between nt 712 and nt 800 were replaced by D-specific
nucleotides, and a D-specific point mutation on polymorphic site nt 916 in exon 6.
This new D variant was previously described by us as
ARRO-I.25 At that time, sequence analysis was not
completed. Further analysis showed the mutation in exon 7 and the
mutant ce-allele in these individuals.
Serologically, this new D variant showed weaker reactions with a
monoclonal anti-D and with polyclonal antiserum used for routine
screening, indicating weak D expression. The genomic features of the
new variant have much resemblance with the recently described weak D
type 4, in which the mutations C602G and T667G are also present, but
the mutation T1025C is not.26 However, with extensive serological testing, the D characteristics of the DAR phenotype gave a
different, not previously described pattern of serological reactions
with MoAbs. The loss of epitopes, as well as the finding of allo-anti-D
formation in an individual with the DAR phenotype, indicates that we
are dealing with a new qualitative D variant with low expression. In 1 of the 40 South African Black donors in whom PCR-based analysis showed
the mutation in exon 4 and 5 but not in exon 7, the expression was not
masked by the presence of a normal D gene. This donor is expected to
present the weak D type 4 phenotype. Preliminary serological results of
this donor suggest a quantitative instead of a qualitative loss of
epitopes, as can be expected from the results of Wagner et
al.26 This is an intriguing observation in view of
the effect of the mutation in exon 7 for the loss of
epitopes. An explanation for this phenomenon can perhaps be found in
the fact that the mutations in exon 4 and 5 do not change the polarity
of the amino acids in the protein. In contrast, the transmembranal
mutation in exon 7 causes the incorporation of a hydrophilic amino acid
(Thr) instead of a hydrophobic amino acid (Ile). This might result in a
severe change in the conformation of the Rh protein, explaining the
described loss of epitopes. In the future, transfection studies will be
performed to study this phenomenon in detail.
The loss of so many D epitopes in DAR is the result of only 3 mutations
in RHD, because from the variant ce-allele only
addition of D epitopes can be expected. The mutations at the 3'
end of exon 4 and the 5' end of exon 5 of the D allele are due to
point mutations. This is suggested by the presence of a normal D intron 4, as shown by sequence analysis. However, aberrant nucleotides may
occasionally be introduced if incorrect mismatch repair of the
heteroduplex DNA takes place during gene conversion.27 So, the DAR mutations on the 3' side of exon 4 and the 5' side
of exon 5 also could be due to the occurrence of heteroduplex repair, rather than to spontaneous point mutations. The same phenomenon has
been described for the glycophorins A and B, which are also encoded by
highly homologous genes.27
The variant ce-gene, ceAR, is characterized by a
mutation in exon 1, a hybrid exon 5, and a mutation in exon 6. The
presence of G48C (Trp16Cys), the C-specific nucleotide in exon 1, without expression of this antigen, frequently occurs in African
Blacks.28 The D-specific nucleotide found in exon 6 of the CE allele is probably caused by a point mutation or
might be due to heteroduplex repair (see above), because restriction
site analysis suggested a normal ce-intron 5. Besides the
ceAR allele, a complete ce-allele was also found, so it
was not possible to test the loss of ce-epitope expression. All
4 individuals were expressing the rare VS,
V+ phenotype. Daniels et al29 has previously
described that the VS mutation (G733, in exon 5) surrounded by
D-specific nucleotides in exon 5 and the V-specific nucleotide
1006G (Gly336) provided the VS, V+
serotype. In this study, RHCE exon 6 was not sequenced.
Therefore, 4 VS, V+ samples of African
Black donors (provided by Dr G.L. Daniels, IBGRL) were sequenced, and,
indeed, these samples also showed the mutation in exon 6 as well as the
C mutation (G48C). These results suggest that the most common genetic
basis of the VS, V+ phenotype is the
ceAR variant. Furthermore, these 4 donors also carried the DAR allele.
The 4 original probands in whom this new serological reaction pattern
was found all proved to be of African Black origin. No Whites carrying
this variant have been found so far during routine screening. This
suggested that more African Blacks might be carriers of these genes.
Therefore, a group of 326 South-African Blacks was screened by genomic
PCR. We found that 4.9% of this group are carriers of a DAR
allele. Five donors (1.5%) had the gene homozygous or in combination
with a D-negative allele, as was shown by the absence of the
amplification products from exons 4 and 5 in the multiplex PCR. These
donors also had the same serological partial D pattern as was shown in
the 37 D-epitope model. The fact that so many South-African Blacks are
carriers of this gene suggests that these donors have an evolutionary
advantage, as described for Duffy involving malaria.30 So
far, no correlations between Rh phenotypes and the occurrence of
malaria have been found. However, these studies have been performed on
immunologically recognized antigens, whereas this new variant is
primarily recognized at the DNA level. The frequency of the DAR
phenotype (1.5%) in the African Black population is much higher than
the frequency of D variants in the White population (0.1% to 0.001%)
and therefore might have an impact on monoclonal reagent design.
Testing the African Blacks for the presence of the ceAR showed
that 6.1% were carriers of this allele.
The finding that the first 4 individuals tested expressed both variant
alleles suggested that these 2 genes were inherited en bloc. By
screening the 326 African Blacks, we expected to find only donors
carrying both mutated alleles or both normal alleles. The screening
results did not confirm this idea, because, besides donors with both
variant alleles, also donors with only the DAR or ceAR
allele were found. Nevertheless, the incidence of the combination is
much higher than is expected to occur by chance, indicating linkage of
DAR and ceAR.
Individuals with the DAR phenotype may form anti-D antibodies when
exposed to a complete D antigen. Despite the loss of so many epitopes,
a complete D antigen does not seem to be highly immunogenic for
individuals expressing DAR. Otherwise, the highly frequent DAR variant
should have been recognized much earlier. A possible explanation for
this low responsiveness may be that the footprints of most anti-Rh (D)
antibodies are related to one another, as was published
recently.31 It is postulated that, in the allo-immune
response against the Rh (D) antigen in different individuals, a similar
and restricted pathway is used. It is tempting to speculate that, in
this variant, the apparent low immunogenicity of the complete D antigen
is due to the fact that the most common pathway could not be used,
because these B cells have been clonally deleted or have become anergic
to avoid self-reactivity. Probably a less-common pathway has produced
the anti-Rh (D) made by the multitransfused donor 4413.
The clinical significance of these anti-D antibodies in this individual
is not yet clear. Nevertheless, pregnant women and recipients of blood
transfusions expressing the DAR variant should be regarded as D
negative. As donors, people expressing DAR should be carefully
distinguished from D-negative donors by the use of selected reagents,
because allo-immunization is likely to occur when administering
erythrocytes expressing the DAR variant to D-negative recipients.
Therefore, donors expressing DAR should be regarded as D positive.
Hemolytic disease of the newborn could occur in fetuses expressing DAR
when carried by an immunized D-negative mother or in fetuses with the
complete D antigen carried by mothers with the DAR phenotype.
Therefore, in the future, anti-D monoclonals for immunoprophylaxis
should be guaranteed to cover this new variant, especially because of
the high incidence of this new variant in a multiethnic society in
which D negativity is found more frequently than in the original
African Black population. In addition, the chance of getting a
population with an even higher frequency of people expressing DAR is
increased, because the expression will not be masked by the presence of
a normal D allele.
| |
ACKNOWLEDGMENT |
J. Hooydonk (South African Blood Transfusion Service) was very helpful
with the collection of samples from the African Black population. The
authors thank him for the collaboration. We are grateful to J. Poole,
C. Green, and G. Daniels from the IBGRL for their very kind
collaboration on this manuscript. We thank M.A.M. Overbeeke,
A.E.G.Kr. von dem Borne, and D. Roos for their comments on
the manuscript.
| |
FOOTNOTES |
Submitted June 1, 1999; accepted August 17, 1999.
The publication costs of this
article were defrayed in part by
page charge payment. This article
must therefore be hereby marked
"advertisement"
in accordance with 18 U.S.C. section
1734 solely to indicate this fact.
Address reprint requests to P.A. Maaskant-van Wijk, PhD,
Bloodbank Rotterdam Location Dordrecht, Laboratory for Transfusion
Science, Albert Schweitzerplaats 5, 3318 AS Dordrecht, The Netherlands.
| |
REFERENCES |
1.
Issit PD:
The blood group system: Additional complexities.
Immunohematology
10:109, 1994
2.
Daniels G:
Human Blood Groups. Oxford, UK, Blackwell Science, 1995
3.
Chérif-Zahar B, Le Van Kim C, Blanchard D, Bailly P, Hermand P, Salmon C, Cartron JP, Colin Y:
Molecular cloning and protein structure of a human blood group Rh polypeptide.
Proc Natl Acad Sci USA
87:6243, 1990
[Abstract/Free Full Text]
4.
Avent ND, Butcher SK, Liu W, Mawby WY, Mallinson G, Parsons SF, Anstee DJ, Tanner MJA:
Localization of the C termini of the Rh (rhesus) polypeptides to the cytoplasmatic face of the human erythrocyte membrane.
J Biol Chem
267:15134, 1992
[Abstract/Free Full Text]
5.
Chérif-Zahar B, Mattéi MG, Le Van Kim C, Bailly P, Cartron J-P, Colin Y:
Localization of the human Rh blood group gene structure to chromosome region 1p34.3-1p36.1 by in situ hybridization.
Hum Genet
86:398, 1991
[Medline]
[Order article via Infotrieve]
6.
Colin Y, Chérif-Zahar B, Le van Kim C, van Huffel R, Cartron JP:
Genetic basis of the RhD-negative blood group polymorphism as determined by Southern blotting.
Blood
82:651, 1991
[Abstract/Free Full Text]
7.
Hyland CA, Wolter LC, Saul A:
Three unrelated Rh D gene polymorphisms identified among blood donors with Rhesus Ccee (r'r') phenotypes.
Blood
84:321, 1994
[Abstract/Free Full Text]
8.
Umenishi F, Kajii E, Ikemoto S:
Molecular analysis of Rh polypeptides in a family with Rh D positive and Rh D negative phenotypes.
Biochem J
299:207, 1994
9.
Faas BHW, Beckers EAM, Wildoer P, Ligthart PC, Overbeeke MAM, Zondervan HA, von dem Borne AEGKr, van der Schoot CE:
Molecular background of VS and weak C expression in blacks.
Transfusion
37:38, 1997
[Medline]
[Order article via Infotrieve]
10.
Blunt T, Daniels G, Carrit B:
Serotype switching in a partially detected RHD gene.
Vox Sang
67:397, 1994
[Medline]
[Order article via Infotrieve]
11.
Daniels G, Green C, Smart E:
Differences between Rh-negative Africans and RhD-negative Europeans.
Lancet
350:862, 1997
[Medline]
[Order article via Infotrieve]
(letter)
12.
Okuda H, Kawano M, Iwamoto S, Tanaka M, Seno T, Okubo Y, Kajii E:
The RHD gene is highly detectable in RhD-negative Japanese donors.
J Clin Invest
100:373, 1997
[Medline]
[Order article via Infotrieve]
13.
Scott M, Voak D, Jones JW, Avent ND, Liu W, Hughes-Jones N, Sonneborn H:
A structural model for RhD epitopes based on serological and DNA sequence data from partial D phenotypes.
Transfus Clin Biol
3:391, 1996
[Medline]
[Order article via Infotrieve]
14.
Scott M:
Rh serology coordinator's report.
Transfus Clin Biol
3:333, 1996
[Medline]
[Order article via Infotrieve]
15.
Flegel WA, Wagner FF:
The frequency of RHD protein variants in Caucasians.
Transfus Clin Biol
3:10S, 1996
16.
Faas BHW, Beckers EAM, Maaskant-van Wijk PA, Overbeeke MAM, van Rhenen DJ, von dem Borne AEGKr, van der Schoot CE:
Molecular characterization of qualitative Rh variants.
Biotest Bull
5:439, 1997
17.
Annex 2:
Rh antibodies. Third International Workshop and Symposium on monoclonal antibodies against human red blood cells and related antigens.
Transfus Clin Biol
6:525, 1996
18.
Murphy JR:
Influence of temperature and method of centrifugation on the separation of erythrocytes.
J Lab Clin Med
82:334, 1973
[Medline]
[Order article via Infotrieve]
19.
Simsek S, de Jong CAM, Cuypers HThM, Bleeker PMM, Westers TM, Overbeeke MAM, Goldschmeding R, van der Schoot CE, von dem Borne AEGKr:
Sequence analysis of cDNA derived from reticulocyte mRNAs coding for Rh polypeptides and demonstration of E/e and C/c polymorphisms.
Vox Sang
67:203, 1994
[Medline]
[Order article via Infotrieve]
20.
Chomczynski P, Sacchi N:
Single step method of RNA isolation by acid guanidium thiocyanate-phenol-chloroform extraction.
Anal Biochem
162:156, 1987
[Medline]
[Order article via Infotrieve]
21.
Sambrook J, Fritsch EF, Maniatis T:
Molecular Cloning: A Laboratory Manual. Cold Spring Harbor, NY, Cold Spring Harbor Laboratory, 1989
22.
Faas BHW, Beckers EAM, Simsek S, Overbeeke MAM, Pepper R, van Rhenen DJ, von dem Borne AEGKr, van der Schoot CE:
Involvement of Ser 103 of the Rhesus polypeptides in the G epitope formation.
Transfusion
36:506, 1996
[Medline]
[Order article via Infotrieve]
23.
Maaskant-van Wijk PA, Faas BHW, de Ruijter JA, Overbeeke MA, von dem Borne AEGKr, van Rhenen DJ, van der Schoot CE:
Genotyping of RHD by multiplex polymerase chain reaction analysis of six RHD-specific exons.
Transfusion
38:1015, 1998
[Medline]
[Order article via Infotrieve]
24.
Avent ND, Martin PG, Armstrong-Fisher SS, Liu W, Finning KM, Maddocks D, Urbaniak SJ:
Evidence of genetics underlying RhD, weak D (Du), and partial D phenotypes as determined by multiplex polymerase chain reaction analysis of the RHD gene.
Blood
89:2568, 1997
[Abstract/Free Full Text]
25.
Hemker M, Ligthart PC, Faas BHW, von dem Borne AEGKr, van der Schoot, van Rhenen DJ, Maaskant-van Wijk PA:
ARRO-I, a new partial D phenotype involving exon 4 and 5.
Vox Sang
74:1331, 1998
(suppl 1)
26.
Wagner FF, Gassner C, Muller Th H, Schonitzer D, Schunter F, Flegel WA:
The molecular basis of weak D phenotypes.
Blood
93:385, 1999
[Abstract/Free Full Text]
27.
Huang CH, Blumenfeld:
MNSs Blood groups and major glycophorins: Molecular basis for allelic variation, in Blood Cell Biochemistry, vol 6. Molecular Basis of Major Blood Group Antigens. New York, NY, Plenum, 1995, p 153
28. Faas BHW, Christiaens GCML, Maaskant-van Wijk PA, Zondervan HA,
von dem Borne AEGKr, van der Schoot CE: The reliability of prenatal RH
and Kell genotyping: A prospective study in different ethnic groups.
Prenatal Diagnosis (submitted)
29.
Daniels GL, Faas BHW, Green CA, Smart E, Maaskant-van Wijk PA, Avent ND, Zondervan HA, von dem Borne AEGKr, van der Schoot CE:
The RH VS and V blood group polymorphisms in Africans: A serological and molecular analysis.
Transfusion
38:951, 1998
[Medline]
[Order article via Infotrieve]
30.
Gelpi AP, King MC:
Duffy blood group and malaria.
Science
191:1284, 1976
[Free Full Text]
31.
Chang TY, Siegel DI:
Genetic and immunological properties of phage-displayed human anti-Rh (D) antibodies: Implications for the Rh (D) epitope topology.
Blood
91:3066, 1998
[Abstract/Free Full Text]
 CiteULike  Connotea  Del.icio.us  Digg  Reddit  Technorati What's this?
This article has been cited by other articles:
|
|
|
|
 
F. Noizat-Pirenne, K. Lee, P.-Y. L. Pennec, P. Simon, P. Kazup, D. Bachir, A.-M. Rouzaud, M. Roussel, G. Juszczak, C. Menanteau, et al.
Rare RHCE phenotypes in black individuals of Afro-Caribbean origin: identification and transfusion safety
Blood,
December 1, 2002;
100(12):
4223 - 4231.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
F. F. Wagner, B. Ladewig, K. S. Angert, G. A. Heymann, N. I. Eicher, and W. A. Flegel
The DAU allele cluster of the RHD gene
Blood,
June 17, 2002;
100(1):
306 - 311.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
F. F. Wagner, A. Frohmajer, B. Ladewig, N. I. Eicher, C. B. Lonicer, T. H. Muller, M. H. Siegel, and W. A. Flegel
Weak D alleles express distinct phenotypes
Blood,
April 15, 2000;
95(8):
2699 - 2708.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
TOP
ABSTRACT
INTRODUCTION