H gene | definition of H gene by Medical dictionary
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Related to H gene: H antigen
in laboratory animals, a gene that can elicit an immune response and thereby cause rejection of a homograft when tissue is transplanted from one individual to another; in humans, histocompatibility genes control HLA antigens.
H gene Transfusion medicine A gene that encodes the enzyme, α-l-fucosyl-transferase, which produces an oligosaccharide, the H antigen; homozygous deficiency of H gene results in a Bombay–or hh phenotype individual who, lacking the above transferase, cannot attach the fucose to the galactose on the precursor H substance. See Bombay phenotype, H antigen, Secretor, Ulex europa.