How frequent is weak D?

Rhesusnegative.net

5 years ago

D– persons either lack RHD, which encodes for the D antigen, or have a nonfunctional RHD gene. Weak D red cells have the D antigen, but have fewer D antigens per cell than normal Rh positive cells. Red cells lacking components of the D antigen have been referred to in the past as D mosaic or D variant. Current terminology more appropriately describes these red cells as partial D. There is 5 phenotype D (D+, D-, Weak D, partial D, Del)

Definition: The weak D phenotype (D^u) is a weakened form of the D antigen that in routine D typing will react with some anti-D but not with others (when an immediate spin or 37° incubation is done). Weak D red cells have the D antigen, but have fewer D antigens per cell than normal Rh positive cells.

Reduced expression of D antigen occurs in an estimated 0.2%–1% of Caucasians. Historically, red blood cell antigens that react with anti-D only after extended testing with the indirect antiglobulin test are called weak D.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3320789/