In Bombay blood group there is no “A” or “B” antigens on red blood cells or in secretions, similar to O’ blood group. But there is no expression H antigen, which is present in blood group O. H antigen, is a precursor carbohydrate from which A and B blood groups are formed.

ABO grouping was done by conventional tube technique after washing the donor and reagent RBCs three times with 0.9% normal saline. Samples which showed Bombay phenotype were confirmed by anti–H lectin and saliva inhibition test.

Total 06 cases (i.e. 0.0034%) of Bombay blood group phenotype were detected

Both forward and reverse blood grouping should be done, so that no patient receives wrong blood transfusion. In emergency situation, it is very difficult to supply Bombay phenotype. Therefore maintaining a rare donor registry (including Bombay phenotype) is the most importance step.