Presence of RHD in serologically D-, C/E+ individuals: a European multicenter study.
BACKGROUND
RHD blood group alleles with reduced or absent antigen expression are a clinically significant and heterogeneous group.


METHODS
To detail population genetics data on apparently D- individuals in central Europe, a six-center study was performed with participants from Austria, Germany, Slovenia, Switzerland, and Russia. A total of 1700 serologically D- samples, positive for C and/or E, were investigated.


RESULTS
Observed unexpressed RHD alleles were 59 RHD-CE-D+ hybrid alleles, 9 apparently regular RHD, 1 new RHD(Y401X); DELs were 8 RHD(M295I), 6 RHD(IVS3+1G>A), and 1 new RHD(X418L); and weakly expressed RHDs were 2 weak D type 5, 1 weak D type 1, 1 RHD category VI type 1, and 1 novel weak D type 26. Although weak D type 26 was shown to have one of the lowest D antigen densities ever observed, it gave rise to anti-D immunization in a transfused D- individual.


CONCLUSIONS
The relative occurrence of RHD among serologically D- samples, positive for C and/or E, differed significantly in the investigated central European regions. Considering the growing use of molecular typing techniques, correct identification of blood group alleles with scarce or missing antigen expression is of utmost clinical importance and requires reliable population-based frequency data.
Gassner
Christoph
C
Central Institute for Blood Transfusion and Immunological Department, General Hospital and University Clinics Innsbruck, Innsbruck, Austria. christoph.gassner@uklibk.ac.at
Doescher
Andrea
A
Drnovsek
Tadeja Dovc
TD
Rozman
Primoz
P
Eicher
Nicole I
NI
Legler
Tobias J
TJ
Lukin
Sergey
S
Garritsen
Henk
H
Kleinrath
Thomas
T
Egger
Bernd
B
Ehling
Rainer
R
Körmöczi
Günther F
GF
Kilga-Nogler
Susanne
S
Schoenitzer
Diether
D
Petershofen
Eduard K
EK
D000483:Alleles; D001483:Base Sequence; D001771:Blood Banks; D005060:Europe; D005260:Female; D005820:Genetic Testing; D005828:Genetics, Population; D006801:Humans; D007518:Isoantibodies / Q000097:blood; D009154:Mutation; D010641:Phenotype; D011247:Pregnancy; D011250:Pregnancy Complications, Hematologic / Q000276:immunology; D012204:Rh-Hr Blood-Group System / Q000235:genetics* / Q000276:immunology; D012426:Russia; D065227:Transfusion Reaction
D007518:Isoantibodies; D012204:Rh-Hr Blood-Group System; C026410:Rho(D) antigen