title: The RoHar antigenic complex is associated with a limited number of D epitopes and alloanti-D production: a study of three unrelated persons and their families.
abstract: BACKGROUND
  the RoHar antigenic complex has been characterized serologically by difficulties in D typing, weak e expression, lack of G antigen, presence of Rh33, a low-frequency Rh antigen, and, more recently, a second low-frequency antigen, FPTT. Allocation to one of the partial D catagories was not considered because of the unuaual reactions of RoHar cells and because anti-D production was not observed in RoHar persons.
  
  
  METHODS
  Three unrelated RoHar donors and their families were studied in detail with special emphasis on D epitope mapping, e and G typing, and screening for antibodies.
  
  
  RESULTS
  Only D epitopes 5 and 6/7 were demonstrable, and D epitopes 1, 2, 3, 4, 8, and 9 seem to be absent in the RoHar complex. In one individual, the presence of alloanti-D with limited specificity, not reacting with RoHar red cells of other individuals, was found 6 months after a second D+ pregnancy.
  
  
  CONCLUSIONS
  The finding of alloanti-D in an RoHar r person supports the concept that the D characteristic of this phenotype is a partial D antigen, which is consistent with the presence of the limited number of D epitopes found in epitope mapping. As has been suggested for other partial D antigens, RoHar individuals should be regarded as D- for the receipt of blood, and pregnant RoHar women who have had D+ pregnancies should receive anti-D prophylaxis.
authors.affiliation: Red Cross Blood Bank and the Department of Hematology, University Hospital, Rotterdam, the Netherlands.
authors.forename: E A
authors.initials: EA
authors.lastname: Beckers
authors.forename: L
authors.initials: L
authors.lastname: Porcelijn
authors.forename: P
authors.initials: P
authors.lastname: Ligthart
authors.forename: H
authors.initials: H
authors.lastname: Vermey
authors.forename: A E
authors.initials: AE
authors.lastname: Von dem Borne
authors.forename: M A
authors.initials: MA
authors.lastname: Overbeeke
authors.forename: D J
authors.initials: DJ
authors.lastname: van Rhenen
mesh_terms: D000939:Epitopes; D006801:Humans; D007518:Isoantibodies / Q000096:biosynthesis*; D012204:Rh-Hr Blood-Group System / Q000235:genetics / Q000276:immunology*
chemical_list: D000939:Epitopes; D007518:Isoantibodies; D012204:Rh-Hr Blood-Group System; C026410:Rho(D) antigen