Wikipedia
Xg antigen system
The XG antigen is a red blood cell surface antigen discovered in 1962.[1] by researchers at the MRC Blood Group Unit.[2]
| Xg blood group | |
|---|---|
Interpretation of antibody panel to detect patient antibodies towards the most relevant human blood group systems, including Xg. | |
| Identifiers | |
| Symbol | XG |
| Alt. symbols | PBDX |
| NCBI gene | 7499 |
| HGNC | 12806 |
| RefSeq | NM_175569 |
| Other data | |
| Locus | Chr. X p22.32 |
The PBDX gene that encodes the antigen is located on the short arm of the X chromosome.[3][4] Since males normally have one X chromosome they are considered hemizygotes. Since women have two copies of the gene and could be heterozygotic for the presence or absence of the functioning gene they could (through the process of lyonisation) express the functioning protein on just some of their red blood cells.[citation needed]
Frequency edit
| Population frequencies of Xa[5] | ||||||
|---|---|---|---|---|---|---|
| Population | Sample N | Xg % | ||||
| Australian Aborigines | 352 | 79 | ||||
| Chinese, mainland | 171 | 60 | ||||
| North Europeans | 5,388 | 66 | ||||
| Indians, Bombay | 100 | 65 | ||||
| Israelis | 201 | 66 | ||||
| American Indians | 308 | 77 | ||||
| New-Guineans | 263 | 85 | ||||
| New York's Afro-Americans | 219 | 55 | ||||
| Sardinians | 322 | 76 | ||||
| Taiwan Chinese | 178 | 53 | ||||
| Taiwan Aborigines | 164 | 38 | ||||
References edit
- ^ Tippett P, Ellis NA (October 1998). "The Xg blood group system: a review". Transfus Med Rev. 12 (4): 233–57. doi:10.1016/S0887-7963(98)80001-1. PMID 9798268.
- ^ Mann, J. D., Cahan, A., Gelb, A. G., Fisher, N., Hamper, J., Tippett, P., Sanger, R., Race, R. R A sex-linked blood group. Lancet. 1962;279:8.
- ^ Ellis NA, Tippett P, Petty A, et al. (November 1994). "PBDX is the XG blood group gene". Nat. Genet. 8 (3): 285–90. doi:10.1038/ng1194-285. PMID 7533029. S2CID 36695727.
- ^ LINDSTEN J, FRACCARO M, POLANI PE, HAMERTON JL, SANGER R, RACE RR (February 1963). "Evidence that the Xg blood group genes are on the short arm of the X chromosome". Nature. 197 (4868): 648–9. Bibcode:1963Natur.197..648L. doi:10.1038/197648a0. PMID 13930842. S2CID 4209911.
- ^ Harrison et al. (1977): Human biology – An introduction to human evolution, variation, growth and ecology. Oxford University Press, Oxford, ISBN 978-0-19-857165-0.