Frequency of Rh Antigen and Phenotypes in Voluntary Blood Donors

A BSTRACT Context: Rh blood group antigens are highly immunogenic and have a propensity to produce alloantibodies in multi-transfused patients. Knowledge of antigen frequency in a population is useful in compatibility issues, population genetics studies, and resolving medico-legal issues. Aims: To determine the frequency of Rh antigens in voluntary blood donors. Settings and Design: A prospective cross-sectional study was conducted on 381 voluntary blood donors in the blood center of a tertiary care center. Methods and Materials: Rh-D typing was conducted by the conventional tube method. Specific monoclonal antisera were used to detect major Rh antigens by the conventional tube method. Statistical Analysis Used: The collected data was recorded on an Excel spreadsheet and analyzed using Statistical Package for Social Sciences (SPSS) software version 20. The results are expressed in frequency and percentage. Results: Among Rh antigens, e was most common (96.6%), followed by D: 94%, C: 87.4%, c: 54.6%, and E: 17.3%. The most common phenotype in Rh-positive donors is DCe/DCe (R1R1) (43.6%), while in Rh-D-negative donors, it is dce/dce (rr) (4.5%). Rare phenotypes were encountered, among which were DCcEE and Rh E/e deletion. The Rh E/e negative antithetical antigens encountered were D CC− (0.5%) and DCc− (0.3%). Conclusions: The database for the antigen frequency of the Rh blood group system in the local blood donor population helps provide antigen-negative units to patients with multiple alloantibodies and compare the frequencies of Rh deletions.