Bombay
Phenotype
Where the individual
inherits both hh genes and lacks the H gene
What is it:
Since the h gene is an
amorph gene – that is it does not code for the production of L-fucosyltransferase - no H
antigen is formed thus no A or B
antigen can form either.
What is this result of the homozygous
condition:
Since the patient lacks the
A and/or B antigens they type as O
with forward typing and they will have anti-A1 and anti-B, as well as anti-A,B and anti-H, so will type out as O
using reverse typing.
What will the patient type as:
They will react with all
cell types (A, B, AB, O) of Donor units,
ASC, and panel cells since they have an anti-H present in plasma.
So how are they detected as being Bombay
not regular type O: