ABSTRACT
H antigen is a precursor to A and B antigens. [Person who lacks A and B antigens has a strong expression of H antigen. In 1 per million population, Bombay phenotype [ lack of A, B, H antigens] is observed, because this group should just experience autologous transfusion. Accurate identification of such people is highly recommended. 2178 persons from 3 different population were selected. One group was Indian population of Tehran [100], 78 persons [from 2 families with Bombay phenotype history, and the third group[2000] was selected as volunteer donors. All of them have O group phenotype.10 cc of whole blood was taken from each subject. Red blood cells washed 3 times with saline and finally samples with 5% dilution were prepared. Each sample was treated with H-Lectin anti-sera, and after 30 minutes agglutination was detected with naked eye and microscope. Only 1 subject among donors had Bombay phenotype. Limitation in Indian population in Tehran caused hinderance detection of new cases of Bombay phenotype. At the end, detection of 1 Bombay phenotype among 2000 donors seems very significant