Correlation between serology and genetics of weak D types in Denmark.
BACKGROUND
To date more than 100 variant D types have been reported and the frequencies vary among populations. Blood donor typing should reveal all donors expressing D antigens, while patient typing should prevent the development of anti-D in patients with a D- or variant D blood type. Serotyping is the standard method to assign transfusion strategies, whereas molecular classification offers a more specific grouping of weak and partial D.


METHODS
Blood donor and patient samples with discrepant results of D phenotyping were collected to investigate the frequency of weak D subtypes in Denmark and to evaluate currently used serologic methods.


RESULTS
Nine different weak D types were identified among the 101 samples. Weak D Types 1, 2, and 3 constituted 80 percent of the analyzed samples and 10 percent of the samples identified as weak D from serology were actually partial D.


CONCLUSIONS
The distribution of weak D types in Denmark was found to resemble the distribution in Northern Germany in respect to the three most prevalent weak D types. Correctly defining all samples that show weak reactions in D typing as weak D or partial D is not possible with serotyping alone; genotyping offers the only exact categorization. Serology is superior for routine blood typing, however.
Christiansen
Mette
M
Department of Clinical Immunology, Aarhus University hospital, Skejby, Denmark. mco@sks.aaa.dk
Samuelsen
Betina
B
Christiansen
Lene
L
Morbjerg
Trine
T
Bredahl
Conny
C
Grunnet
Niels
N
D000595:Amino Acid Sequence; D001782:Blood Donors; D001788:Blood Grouping and Crossmatching / Q000379:methods* / Q000592:standards; D003718:Denmark; D006801:Humans; D016133:Polymerase Chain Reaction; D012204:Rh-Hr Blood-Group System / Q000145:classification / Q000235:genetics / Q000276:immunology*; D012698:Serologic Tests
D012204:Rh-Hr Blood-Group System; C026410:Rho(D) antigen