title: RhCE protein variants in Southwestern Germany detected by serologic routine testing.
abstract: BACKGROUND
  Variant RHCE alleles with diminished expression of C, c, E, and e antigens have been described and indicate the genetic diversity of this gene locus in several populations. In this study the molecular background of variant RhCE antigens identified by standard serologic routine testing in German blood donors and patients was determined.
  
  
  METHODS
  Samples from blood donors and patients were routinely analyzed for RhCE phenotype using the PK7200 analyzer with two sets of monoclonal anti-C, -c, -E, and -e reagents. Samples with confirmed variant RhCE antigens were analyzed by nucleotide sequencing of the 10 RHCE exons. A multiplex polymerase chain reaction with sequence-specific priming (PCR-SSP) method was established for rapid typing of the rare RHCE alleles.
  
  
  RESULTS
  We identified 43 samples with serologic RhCE variants. Molecular analysis revealed variant RHCE alleles in 34 samples. Altogether 22 RHCE alleles were detected; 10 have not been published before. Twenty alleles harbored distinct single-nucleotide substitutions, 18 of which encoded amino acid changes and 2 of which occurred in noncoding regions. Two samples represented RHCE-D-CE hybrid alleles involving different segments of the RHCE Exon 5. A multiplex PCR-SSP screening for 17 RHCE alleles was negative in 1344 samples of the DNA bank GerBS. The cumulative phenotype frequency was estimated between 1 in 488 (0.20%) and 1 in 8449 (0.012%).
  
  
  CONCLUSIONS
  Single-amino-acid substitutions were the molecular basis for variant RhCE antigen expression in most samples. Nucleotide substitutions in RHCE exons were excluded as possible mechanism of diminished RhCE antigen expression in one-fifth of the serologically identified samples.
authors.affiliation: German Red Cross Blood Donor Service, Baden-Württemberg-Hessen, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Bugert
authors.forename: Erwin A
authors.initials: EA
authors.lastname: Scharberg
authors.forename: Christof
authors.initials: C
authors.lastname: Geisen
authors.forename: Inge
authors.initials: I
authors.lastname: von Zabern
authors.forename: Willy A
authors.initials: WA
authors.lastname: Flegel
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000483:Alleles; D019943:Amino Acid Substitution / Q000235:genetics; D001782:Blood Donors; D005260:Female; D005787:Gene Frequency; D014644:Genetic Variation; D005858:Germany; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D012204:Rh-Hr Blood-Group System / Q000235:genetics*; D044465:White People; D055815:Young Adult
chemical_list: C066468:RHCE protein, human; D012204:Rh-Hr Blood-Group System