OH

Interpretation & conclusion: The anti-H clones thus produced indigenously provided a potent reagent in distinguishing normal O group from Bombay phenotype individuals.

The antigen H is present on all human red cells in diminishing amounts in the order as O>[A.sub.2]>B> [A.sub.2]B>[A.sub.1]>[A.sub.1]B and is absent in Bombay phenotype individuals (1).

The anti-H generated indigenously clearly distinguished "O' group from Bombay Phenotype. The material also showed dosage effect with A,B,O cells depending upon the strength of H antigen present on the surface of these red cells (Table II).

H-deficient Bombay phenotype is rare since it occurs in about 1 in 10,000 individuals in India and 1 per 1,000,000 in Europe (4).

To label and diagnose a case as typical Bombay Phenotype certain specialized tests like absorption-elution studies, titration of naturally occurring antibodies at different temperatures, inhibition of anti-H by O saliva secretor and secretor status were performed as described by Bhatia 1977.