Weak D  (Du) antigen
•When the D antigen is not detected using standard anti-D testing procedures.
•What is it:
•What may cause it:
•Genetic – weak gene expression (more common in Africans)
•Position effect – when C antigen is in trans position to D
•Partial D – parts of the D antigen are missing
•For all donor units – labeled positive if weak D is detected
•When is it important to confirm a weak D:
•For all newborns
•For all pregnant women – (OB panel)