Sangeeta Pathak: The Bombay Blood Group as a Very Rare Phenotype
Sangeeta Pathak, Senior Director and Head at Max Healthcare, shared a post on LinkedIn:
“What is a Bombay blood group:
The Bombay blood group (Oh or hh) is a very rare blood-group phenotype first described in Bombay (Mumbai), India.
People with the Bombay phenotype lack the H antigen on their red blood cells.
The H antigen is the precursor needed to form the A or B antigens.
Therefore, even if their genes are for A or B, their red cells do not express A or B antigens, so routine ABO typing can misleadingly appear to show group O.
They also usually have anti-H antibodies in their plasma, in addition to anti-A and anti-B.
Because ordinary group O blood contains H antigen, a person with Bombay phenotype generally cannot safely receive ordinary O blood.
They need compatible blood from another Bombay-phenotype donor.
How common is it in India?
The Bombay phenotype is estimated to occur in approximately 1 in 10,000 people in India, or about 0.01% of the Indian population.
Its frequency is higher in some regions and communities.
For comparison, worldwide it is much rarer – roughly 1 in 1,000,000 people, although estimates vary by population.
In short:
Bombay blood group is equal to hh/Oh phenotype plus absence of H antigen plus anti-H antibody plus approximately 0.01% (1 in 10,000) in India.
Very happy to be featured in ‘MedInsider’ a monthly news read by Max Hospitals for – Doctors setting benchmarks by managing challenging medical cases extraordinarily.
Do read the story given below related to Bombay blood group .”

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