Polymorphisms of RhD(Va) and a new RhD(Va)-like variant found in Japanese individuals.
OBJECTIVE
Red cell type RhD(Va) lacks epD1 and 5 and is encoded by hybrid RHD-CE(5)-D alleles. We analyzed RhD(Va) and RhD(Va)-like samples in Japanese blood donors.


METHODS
Ten RhD(Va) samples lacked epD1 and 5 and 3 RhD(Va)-like variants also lacked, epD2 and a part of 6/7. We identified the full-length nucleotide sequences of the complementary DNA (cDNA) synthesized from 4 samples: 3 of type D(Va) and the 4th a D(Va)-like variant.


RESULTS
Although their sequences differed from each other, all the substitutions were exclusively in exon 5. Three D(Va) samples had hybrid RHD-CE(5)-D alleles, but the D(Va)-like variant had a unique nucleotide substitution with a single amino acid change, E233K. Exon 5 of the genomic DNA from all 13 samples was analyzed by sequencing. No other sequences were identified.


CONCLUSIONS
All RhD(Va) and RhD(Va)-like variants had the substitution for E233. E233 seems to be a determinant of epD1 and 5. A new category of RhD variant, DYO, was identified.
Hyodo
H
H
Japanese Red Cross Central Blood Center, Tokyo, Japan.
Ishikawa
Y
Y
Kashiwase
K
K
Ogawa
A
A
Watanabe
Y
Y
Tsuneyama
H
H
Toyoda
C
C
Uchikawa
M
M
Akaza
T
T
Fujii
T
T
Kozuma
S
S
Taketani
Y
Y
Juji
T
T
D019943:Amino Acid Substitution; D004252:DNA Mutational Analysis; D018076:DNA, Complementary; D005091:Exons; D014644:Genetic Variation; D006801:Humans; D007564:Japan; D015514:Oncogene Proteins, Fusion / Q000097:blood / Q000235:genetics*; D017354:Point Mutation; D011110:Polymorphism, Genetic; D011993:Recombinant Fusion Proteins; D012204:Rh-Hr Blood-Group System / Q000235:genetics*; D017422:Sequence Analysis, DNA
D018076:DNA, Complementary; D015514:Oncogene Proteins, Fusion; D011993:Recombinant Fusion Proteins; D012204:Rh-Hr Blood-Group System; C117760:RhD fusion protein, human; C026410:Rho(D) antigen