Summary:
Two cases of the rare blood group “Bombay phenotype” are
discussed here. This rare blood group, Bombay (Oh) was first
established by Bhende et al in Bombay (Mumbai), in 1952.In
the ABO (ABH) blood group system, the ‘O’ antigen represents
the lack of A or B antigens; however it has the most amount of
H antigen. If the H gene is absent, which is extremely rare, H
substance can not be formed and subsequent A and B antigens
can not also be formed. Absence of H gene results in the
Bombay phenotype (Oh) 1-6, 7-13. Individuals with the Bombay
phenotype develop anti-H antibodies. This is the reason that
undetected Bombay individuals (typically typed as O
individuals) will be cross match incompatible with O