Premium
The low‐frequency MNS blood group antigens Ny a (MNS18) and Os a (MNS38) are associated with GPA amino acid substitutions
Author(s) -
Daniels G.L.,
Bruce L.J.,
Mawby W.J.,
Green C.A.,
Petty A.,
Okubo Y.,
Kornstad L.,
Tanner M.J.A.
Publication year - 2000
Publication title -
transfusion
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.045
H-Index - 132
eISSN - 1537-2995
pISSN - 0041-1132
DOI - 10.1046/j.1537-2995.2000.40050555.x
Subject(s) - exon , microbiology and biotechnology , antigen , monoclonal antibody , epitope , hemagglutination assay , biology , loss of heterozygosity , genetics , antibody , gene , allele , titer
BACKGROUND: Antigens of the MNS blood group system are located on two sialoglycoproteins, GPA and GPB, encoded by GYPA and GYPB . The molecular backgrounds of the low‐frequency antigens Ny a and Os a are not known. STUDY DESIGN AND METHODS: Immunoblotting and a monoclonal antibody‐specific immobilization of erythrocyte antigens (MAIEA) assay were used to analyze Os a . PCR‐amplified products of the coding exons of GYPA were studied by single‐strand conformation polymorphism analysis, and exon 3 was sequenced. Synthetic peptides were used in hemagglutination‐inhibition tests. RESULTS: Sequencing of GYPA exon 3 of two unrelated Ny(a+) persons revealed heterozygosity for a T194A base change encoding an Asp27Glu substitution. Immunoblotting with anti‐Os a and an MAIEA assay with MoAbs to GPA showed that Os a is on GPA. Sequencing exon 3 of an Os(a+) person from the only family with Os a revealed heterozygosity for a C273T base change encoding a Pro54Ser substitution. A synthetic peptide representing part of GPA with the Os a mutation (VRTVYP S EEETGE) completely inhibited anti‐Os a , whereas the control peptide (VRTVYP P EEETGE) did not inhibit anti‐Os a . CONCLUSION: Ny a and Os a are low‐frequency antigens of the MNS blood group system that represent Asp27Glu and Pro54Ser substitutions in GPA, respectively.