title: Novel GYP(A-B-A) hybrid gene in a DANE+ person who made an antibody to a high-prevalence MNS antigen.
abstract: BACKGROUND
  The glycophorin (GP) molecule associated with the GP.Dane phenotype is a GP(A-B-A) hybrid that contains some amino acids encoded by the Pseudoexon 3 of GYPB and Asn(45) of GPA and carries the low-prevalence MNS antigens DANE and Mur. Serum from a woman of English ancestry contained an immunoglobulin M alloantibody to a high-prevalence MNS antigen, and the purpose of this study was to identify the molecular basis of her phenotype.
  
  
  METHODS
  Hemagglutination, Western blotting, and DNA analyses were performed by standard methods.
  
  
  RESULTS
  Tests of the proband's RBCs with monoclonal antibodies indicated a change of amino acids between positions 27 and 55 of GPA. Her RBCs expressed M, s, Mur, and DANE antigens and were M(g)-negative. The antigen recognized by her antibody was sensitive to treatment with papain, ficin, and trypsin and resistant to alpha-chymotrypsin and dithiothreitol. Sequencing of DNA from the proband revealed a sequence of nucleotides identical to the GYP(A-B-A) encoding GP.Dane but without the adenyl nucleotide substitution, which has been predicted to change Ile(46) of GPA to Asn(45). Testing of her immediate family revealed the presence of an M(k) gene.
  
  
  CONCLUSIONS
  The proband had a novel GYP(A-B-A) encoding a DANE+ GP that is in cis to GYPB(s) and in trans to M(k). The high-prevalence antigen lacking from this GP.Dane phenotype and recognized by the proband's serum is called ENDA (ISBT Number MNS44). Our results indicate that the change of Ile(46) of GPA to Asn(45) of GP.Dane is not required for expression of the DANE antigen.
authors.affiliation: New York Blood Center, New York, New York, USA.
authors.forename: Randall W
authors.initials: RW
authors.lastname: Velliquette
authors.forename: Poonsub
authors.initials: P
authors.lastname: Palacajornsuk
authors.forename: Kim
authors.initials: K
authors.lastname: Hue-Roye
authors.forename: Sally
authors.initials: S
authors.lastname: Lindgren
authors.forename: Sarah
authors.initials: S
authors.lastname: Ilstrup
authors.forename: Carole
authors.initials: C
authors.lastname: Green
authors.forename: Christine
authors.initials: C
authors.lastname: Lomas-Francis
authors.forename: Marion E
authors.initials: ME
authors.lastname: Reid