Red blood cell phenotyping of blood donors in Islamabad, Pakistan

Background: There are 33 blood groups identified so far representing more than 300 antigens. The blood transfusion services in resource-limited countries including Pakistan only test for ABO and RhD antigens during cross-matching. However, the transfusion of ABO-RhD compatible but unknown phenotype blood may result in alloimmunization, especially in multi-transfused patients. Aims: The aim of this study is to investigate the prevalence of clinically significant minor blood group antigens in population of Islamabad, Pakistan. Settings and Design: A prospective study was conducted at the Department of Blood Transfusion Services, Islamabad. Subjects and Methods: Blood samples from 625 randomly selected blood donors were collected for extended antigen typing. Blood grouping was performed using commercially available antisera. The statistical analysis was done using SPSS version 20.0. Gene frequencies were calculated using the Hardy–Weinberg equation. Results: Of the 625 blood donors, 575 were RhD positive (92%) and 50 (8%) were RhD negative. The frequencies of A, B, AB, and O antigens were (24.64%), (34.72%), (9.28%), and (31.36%), while antigen frequency of K was 4%, Duffy (Fya) 58.24%, Duffy (Fyb) 39.84%, Kidd (Jka) 65.28%, Kidd (Jkb) 42.24%, M 86.88%, N 46.24%, S s49.44%, and s 30.4%. Calculated gene frequency for Kell K was (0.04), Duffy Fya (0.481), Fyb (0.519), Kidd JKa (0.538), JKb (0.462), M (0.699), N (0.301), S (0.445), and s (0.556). Conclusions: The current study depicts the prevalence of the blood group antigens among Pakistani blood donors to be statistically different from those in Caucasians, Chinese, and African populations