title: DIII Type 7 is likely the original serologically defined DIIIb.
abstract: BACKGROUND
  Due to their homology, close proximity, and opposite orientation, RHD and RHCE can exchange nucleotides giving rise to variant alleles. Some of these variants encode the so-called partial phenotypes. The DIII partial D category has been subdivided into DIIIa, DIIIb, DIIIc, DIII Type 4, DIII Type 6, and DIII Type 7. During DNA-based screening tests, we identified a second example of DIII Type 7 in a Dce donor from South Africa. Our study describes hemagglutination tests on this sample and raises a question regarding the molecular basis of the originally defined DIIIb category.
  
  
  METHODS
  Hemagglutination and DNA testing were performed by standard techniques.
  
  
  RESULTS
  Red blood cells from this DIII Type 7 donor typed D+C-E-c+e+G-, DAK+ and did not react with anti-D made by people with the DIII phenotype. The allele is RHD*DIII 150C, 178C, 201A, 203A, 307C, 410T, 455C, 602G, 667G.
  
  
  CONCLUSIONS
  Based on the serotype and ethnicity (black African), it is likely that DIII Type 7 is the originally defined DIIIb category.
authors: Laboratory of Immunohematology, New York Blood Center, New York, New York 10065, USA.
authors: Christine
authors: C
authors: Lomas-Francis
authors: Christine
authors: C
authors: Halter Hipsky
authors: Randall W
authors: RW
authors: Velliquette
authors: Marion E
authors: ME
authors: Reid
mesh_terms: D000483:Alleles; D005091:Exons / Q000235:genetics; D006384:Hemagglutination; D006386:Hemagglutination Tests; D006801:Humans; D012204:Rh-Hr Blood-Group System / Q000235:genetics*
chemical_list: C066468:RHCE protein, human; D012204:Rh-Hr Blood-Group System; C026410:Rho(D) antigen