Distribution of ABO and rhesus (D) blood group antigens among blood donors at a tertiary care teaching hospital blood bank in south India

Background: The ABO and Rhesus (Rh) blood group systems are important for transfusion of blood and its components, organ transplantation, genetic studies and in medico-legal issues. Despite the long list of several other blood groups discovered so far, the knowledge and distribution of ABO and Rh-D blood group are essential for effective management of blood bank inventory. Methods: We retrospectively studied the distribution of ABO and Rh blood group antigens in donors presenting to our tertiary care teaching hospital blood bank in south India during the period January 2007 to August 2014. Blood group was determined by commercially available standard monoclonal antisera by test tube agglutination technique. Results: A total of 49,110 donor samples were tested during the study period for ABO grouping and Rh-D typing. Out of these 96.9% were males. The frequency of O, B, A, AB and Bombay blood groups were 41.7%, 32.2% 20%, 6.1% and 0.03% respectively. Rh (D) positive and negative blood groups were seen in 92.8% and 7.2% respectively. The allele frequencies of the IA, IB and IO alleles were 0.1398, 0.2148 and 0.6454 respectively. In case of Rh-D group, the calculated gene frequencies for ID and Id were 0.7321 and 0.2679 respectively. Conclusion: Knowledge of blood group systems as documented in the present study helps in efficient manage- ment of blood bank and transfusion services in emergencies.