Partial expression of RHc on the RHD polypeptide.
BACKGROUND
In the human Rh blood group system, c is, after D, the most immunogenic antigen.


METHODS
The background of a new partial c phenotype (D(c)), identified on the RBCs of two unrelated white persons, was studied. This was done by analyzing the reactivity of the RBCs from the donors with anti-c reagents, by performing sequence analysis, and by carrying out transduction studies.


RESULTS
Serologic results suggested the existence of a new partial c phenotype. Genomic DNA and cDNA analysis revealed a normal RHCe allele, a normal RHD allele, and an RHD allele that carried two point mutations: 307T>C and 329T>C (the latter known to be associated with the DVII, Tar-positive phenotype). No normal RHc allele was found. Thus, it was most likely that c is encoded by the mutated RHD allele (phenotype DD(c)CCee). Indeed, subsequent transduction of K562 erythroleukemic cells with an RHD cDNA carrying the 307T>C point mutation (leading to S103P) resulted in the expression of c.


CONCLUSIONS
In the human Rh system, P103 is involved in the expression of c. Moreover, c can be expressed in vivo on the D polypeptide.
Faas
B H
BH
Department of Experimental Immunohematology, Central Laboratory of the Netherlands Blood Transfusion Service.
Beuling
E A
EA
Ligthart
P C
PC
van Rhenen
D J
DJ
van der Schoot
C E
CE
D000483:Alleles; D001782:Blood Donors; D018076:DNA, Complementary / Q000235:genetics; D000939:Epitopes; D004912:Erythrocytes / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D007519:Isoantigens / Q000235:genetics*; D009154:Mutation; D010455:Peptides / Q000235:genetics; D012204:Rh-Hr Blood-Group System / Q000235:genetics*; D014162:Transfection; D014407:Tumor Cells, Cultured
D018076:DNA, Complementary; D000939:Epitopes; D007519:Isoantigens; D010455:Peptides; D012204:Rh-Hr Blood-Group System; C026410:Rho(D) antigen