Molecular basis of D variants in Chinese persons.
BACKGROUND
Most studies of the molecular basis of D variants have been conducted in Caucasian and African populations. There are limited data on the molecular basis for D variants in Chinese populations.


METHODS
With a blended monoclonal anti-D and a sequential slide and tube typing protocol, red blood cells from greater than 99 percent of Han Chinese were tested for the D antigen. Samples that agglutinated weakly by tube method or that reacted only by indirect antiglobulin test (IAT) were classified as D variants. The D variant was tested by an RHD polymerase chain reaction with sequence specific primers and by gene sequencing to distinguish and characterize weak D and partial D alleles.


RESULTS
Of 305,572 samples from individual donations (305,475 [99.97%] were ethnic Han and 97 [0.032%] were ethnic minorities), 304,134 (99.53%) typed as D+. Five (0.0016%) typed as D variants (weak agglutination by tube). By IAT an additional 32 (0.0105%) typed as D variants and 1401 (0.46%) typed as D-. Weak D type 15 and RHD(K409K) alleles represented 72.7 percent of all weak D phenotypes. All partial D phenotypes were DVI Type 3 or DV. Three new weak D alleles carrying 594A>T and 602C>G (weak D Type 51), 92T>C (weak D type 52), and 740T>G (weak D type 53) mutations, respectively, were identified.


CONCLUSIONS
There are significant differences in the frequencies and molecular characteristics of D variants among indigenous Chinese populations, compared to Caucasian and African populations, which must be considered when developing clinical practices related to D variant blood donors, transfusion recipients, or obstetrical patients.
Yan
Lixing
L
Institute of Transfusion Medicine, Blood Center of Zhejiang Province, and Key Laboratory of Blood Safety Research, Ministry of Health, Hangzhou, Zhejiang, China. ylx@zjb.org.cn
Wu
Junjie
J
Zhu
Faming
F
Hong
Xiaozhen
X
Xu
Xianguo
X
D000483:Alleles; D044466:Asian People / Q000235:genetics*; D001788:Blood Grouping and Crossmatching; D006801:Humans; D020641:Polymorphism, Single Nucleotide; D012204:Rh-Hr Blood-Group System / Q000235:genetics*; D017422:Sequence Analysis, DNA
D012204:Rh-Hr Blood-Group System; C026410:Rho(D) antigen