Genotyping RhD variations in Turkish population and investigate the correlation of molecular results with serologic identification

Due to its strong immunogenicity, "RhD" is the most important erythrocyte antigen after ABO antigens. Some mutations in the RHD gene lead to "D variant" phenotypes. RhD variations are categorized in two main groups as "Weak D" and "Partial D". Incorrect detection of RhD variations as Rh(-) in the donor or Rh(+) in the recipient can lead to hemolytic transfusion reactions, anti-D alloimmunization, and hemolytic disease of the fetus and newborn (HDFN). In order to prevent the risk, it is recommended to make a weak D/partial D differentiation in patients and pregnant women. Molecular typing is accepted as the reference method for weak D and partial D discrimination. However, it is also accepted that a safe distinction can be made by serological method using panels of monoclonal antibodies. The aim of this study was to determine the most frequent RhD variations in our country and to compare the reliability of the serological method with the molecular method in typing RhD variations. In our study, the frequency of weak D and partial D was found to be close to each other (48.8% - 51.2% respectively), and the most common weak D variation was found to be "weak D type 1" and partial D variation as "weak D type 15". When molecular typing is taken as the gold standard, it has been shown that weak D/partial D discrimination and partial D typing cannot be reliably performed by serological method.