Abstract

 Background and Objectives

 Knowing the frequency of D,C,E,c,e antigens is necessary for population studies and plays a significant role in paternity tests. The purpose of this research is to determine the frequency of Rh antigens and their phenotypes in Khorramabad blood donors and to set up the data bank of individuals lacking the very common antigens.

 Materials and Methods

 The study was carried out as census on 1236 blood donors referring to Khorramabad Blood Center. Appropriate cell suspensions were incubated with several Rh antiserums then, based on the type of reactions observed and most probable genotypes identified by reference to tables of Rh antigens frequency in black and white populations, phenotypes for main antigens were determined.

 Results

 Out of all observed reactions, the most common ones were associated with the e antigen (94.34% , CI 95%= 91.57-97.10) and the least with the E antigen (43.5%). As to D antigens, 92.88% (CI 95% = 90.14-95.65) of individuals were positive and 7.4% were negative. The results were 73.5% and 71.2% for C and c antigens, respectively.

 Conclusions

 A 92.88% frequency for D antigen in Khorramabad city blood donors indicates a high regional difference in frequency. As a result, Rh negative blood units in the region deserve much more attention. In the meantime, the relatively significant frequency of e negative donors in the region more than ever emphasizes the necessity of setting up an e negative blood bank.

 Key words: phenotype, Rhesus Blood-Group System, Blood donors , Iran