Version 2.77


The H antigen is produced by a specific fucosyltransferase. Depending upon a person's ABO blood type, the H antigen is converted into either the A antigen, B antigen, or both. If a person has blood group O, the H antigen remains unmodified. Therefore, the H antigen is present in the highest amounts in blood type O and in the least amounts in blood type AB. The history and biochemical nature of the H antigen is entangled with that of the ABO and Lewis blood group systems. The recognition of the Hh blood group probably begins with the discovery by Bhende et al. (1952) of the first three individuals who completely lacked A and B antigens but were not group O. This null phenotype was named "Bombay" after the city where it was found. Although the Bombay phenotype is extremely rare in most populations, a number of examples have been found in India over the years. Early suggestions were that this type was due to a new allele at the ABO locus, but others suggested an inhibitor gene and finally the possibility of a genetically independent but related gene. We now know that the Bombay phenotype is due to a recessive gene at the H locus; ie. h and is therefore referred to as Oh. Subsequently, intermediate form of the H gene have been found and these individuals are called "para-Bombays". Source: National Library of Medicine, H NOS

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Tag Language Translation
zh-CN Chinese (China) H 型 未作说明的
Synonyms: H NOS;H 型 NOS;H 未作说明的
fr-CA French (Canada) H NS
es-ES Spanish (Spain) H NOS
it-IT Italian (Italy) H NAS
tr-TR Turkish (Turkey) H NOS
ru-RU Russian (Russian Federation) H не указанный в другом месте
nl-NL Dutch (Netherlands) H NOS
fr-BE French (Belgium) H SAI