Prevalence of red blood cell major blood group antigens and phenotypes among Omani blood donors

Objectives: Most literature on the frequencies of red blood cell (RBC) phenotypes are published in Europeans and Africans countries, with the frequencies in the Omani population unknown. We sought to determine the prevalence of RBC blood group phenotypes among Omani blood donors. Methods: Blood group ABO, RhD type, and phenotyping were performed for 21 blood group antigens on enrolled blood donors. The following antigens were assessed serologically: Rh (C, c, E, e), Kell (K, k, Kp^a, Kp^b), Kidd (Jk^a, Jk^b), Duffy (Fy^a, Fy^b), Lewis (Le^a, Le^b), Lutheran (Lu^a, Lu^b), MNS (M, N, S, s), and P1. Results: A total of 337 Omani blood donors were tested. The most common blood group was O+ (44.9%). Among the tested blood donors studied, 89.3% were RhD positive with R1r being the most common Rh phenotype. The k antigen was found at a frequency of 99.4%, while 4.5% of the blood donors studied were K+. The most common phenotype in the Duffy blood group system was Fy(a-b-), while the most common phenotypes in the Kidd and MNS blood group systems were Jk(a+b+) and M+N-S+s+ at 47.0% and 22.6%, respectively. The Le(a+) and Le(b+) antigens were found in 21.7% and 67.3% of the blood donors, respectively. One Jk(a-b-), one Le(a+b+), and two Lu(a-b-) individuals were identified. Conclusion: This is the first study to examine the frequencies of RBC phenotypes among the Omani blood donors. The study’s results show Duffy blood group frequencies that resemble what has been reported in the African population, and higher frequencies of the rare null phenotypes compared to European populations.