[The family investigation of a weak D type 15 donor].
OBJECTIVE
To study the genetic feature of weak D type 15 allele (RHD845A) in a Chinese family.


METHODS
Rh D, C, c, E and e phenotypes of 4 members in a weak D type 15 family were tested by serological and polymerase chain reaction (PCR), D antigen was proven by indirect antiglobulin test. A pair of primers specific for RHD845A were designed, and a sequence specific primer-PCR (PCR-SSP) method was established to detect RHD845A allele in all family members. Subsequently the dual-tube PCR method was used to determine the RHD zygosity of 4 members.


RESULTS
The RHD845A allele existed in all 4 family members and the RHD zygosity test showed that all members were RHD +/RHD + homozygous. The parents and nephew possessed one normal RHD gene as RHD845A allele carriers, which caused RhD positive. The proband and his old-sister took two RHD845A alleles, which caused weak D phenotype.


CONCLUSIONS
The proband is the weak D type 15 allele homozygous. The weak D type 15 gene is an ancestral allele, but not a mutation.
Xiong
Wen
W
Shenzhen Blood Center and Institute of Transfusion Medicine, Shenzhen, Guangdong, 518035 PR China. xwen68@yahoo.com.cn
Qin
Jian-jiang
JJ
Liu
Yan
Y
Zhou
Yi-yan
YY
Shao
Chao-peng
CP
D000328:Adult; D000483:Alleles; D005192:Family Health; D005260:Female; D005838:Genotype; D006720:Homozygote; D006801:Humans; D008297:Male; D010375:Pedigree; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D012204:Rh-Hr Blood-Group System / Q000235:genetics*
D012204:Rh-Hr Blood-Group System; C026410:Rho(D) antigen