Identification of RHD alleles with the potential of anti-D immunization among seemingly D- blood donors in Upper Austria.

Background: Aberrant RHD alleles leading to a reduced expression of D antigen on the red blood cell (RBC) surface may be mistyped as D- by serology. To quantify the occurrence of weak D, DEL, and D+/- chimera among apparent D- first-time blood donors, polymerase chain reaction (PCR) screening was implemented as a routine service.

Study Design And Methods: A total of 23,330 pretyped D- samples were tested for RHD markers in Exons 4, 7, and 10 in pools of 20 by PCR.