RESUMO
Background & Objectives: Out of total 328 antigens recognized by the International Society of Blood Transfusion (ISBT), ABO and RhD antigens are the most important from the transfusion medicine perspective. The present study was conducted with larger sample size than prior studies to determine frequencies of ABO and Rh alleles and obtain distribution of ABO and RhD blood group pattern among blood donors. Methods: A retrospective study was conducted in the Department of IHBT, Civil Hospital, Ahmedabad from October 2007 to September 2012. ABO grouping and RhD typing was done using conventional tube technique on a total of 109771 donors. Commercial anti-sera and in-house prepared cells were used for cell and serum grouping respectively in those tests. Departmental Standard Operating Procedures (SOPs) were followed for each aspect of testing. Observed ABO and RhD antigen frequencies were noted. Bernstein and Hardy-Weinberg equations were applied to determine the allele frequencies of ABO and RhD respectively. Results: Blood group B has the highest prevalence (35.81%) in the population under study followed by O (32.74%), A (22.68%) and AB (8.77%). Female donors comprised only 1.75% of the sample size. Rh D positivity was noted in 94.48% donors. Conclusion: Results obtained were quite similar to prior studies from Ahmedabad with smaller sample size. Remarkable differences were noted as compared with western population. The data generated in the present study combined with several other studies of different geographical region of India has significant implications in inventory management of blood transfusion services.