XK (protein)
| XK (protein) | |||||||
|---|---|---|---|---|---|---|---|
| Identifiers | |||||||
| Symbol | XK | ||||||
| Alt. symbols | XKR1, Kx, X1k | ||||||
| NCBI gene | 7504 | ||||||
| HGNC | 12811 | ||||||
| OMIM | 314850 | ||||||
| PDB | BAE48708 | ||||||
| RefSeq | NM_021083 | ||||||
| UniProt | P51811 | ||||||
| Other data | |||||||
| Locus | Chr. X p21.2-p21.1 | ||||||
| |||||||
XK (also known as Kell blood group precursor) is a protein found on human red blood cells and other tissues which is responsible for the Kx antigen which helps determine a person's blood type.
Clinical significance
The Kx antigen plays a role in matching blood for blood transfusions.
Mutation of XK protein may lead to McLeod syndrome,[1] a multi-system disorder characterized by hemolytic anemia, myopathy, acanthocytosis, and chorea.[2]
XK is located on the X chromosome (cytogenetic band Xp21.1) and absence of the XK protein is an X-linked disease.[3]
Clinical diagnostic
Clinical testing in patient care for Kx antigen follows published minimum quality and operational requirements,[4] similar to red cell genotyping for any of the other recognized blood group systems. Molecular analysis can identify gene variants (alleles) that may affect Kx antigen expression on the red cell membrane.
Function
XK is a membrane transport protein of unknown action.[5]
References
- ^ Arnaud L, Salachas F, Lucien N, et al. (March 2009). "Identification and characterization of a novel XK splice site mutation in a patient with McLeod syndrome". Transfusion. 49 (3): 479–84. doi:10.1111/j.1537-2995.2008.02003.x. PMID 19040496. S2CID 27198922.
- ^ Malandrini, A; Fabrizi, GM; Truschi, F; Di Pietro, G; Moschini, F; Bartalucci, P; Berti, G; Salvadori, C; et al. (1994). "Atypical McLeod syndrome manifested as X-linked chorea-acanthocytosis, neuromyopathy and dilated cardiomyopathy: report of a family". Journal of the Neurological Sciences. 124 (1): 89–94. doi:10.1016/0022-510X(94)90016-7. PMID 7931427. S2CID 27859436.
- ^ Ho, MF; Monaco, AP; Blonden, LA; Van Ommen, GJ; Affara, NA; Ferguson-Smith, MA; Lehrach, H (1992). "Fine mapping of the McLeod locus (XK) to a 150-380-kb region in Xp21". American Journal of Human Genetics. 50 (2): 317–30. PMC 1682457. PMID 1734714.
- ^ Standards for Molecular Testing for Red Cell, Platelet, and Neutrophil Antigens (7 ed.). Association for the Advancement of Blood & Biotherapies. January 1, 2025. ISBN 978-1-56395-516-7.
- ^ Jung, HH; Russo, D; Redman, C; Brandner, S (2001). "Kell and XK immunohistochemistry in McLeod myopathy". Muscle & Nerve. 24 (10): 1346–51. doi:10.1002/mus.1154. PMID 11562915. S2CID 44749645.
External links
- GeneReviews/NCBI/NIH/UW entry on McLeod Neuroacanthocytosis Syndrome
- XK at BGMUT Blood Group Antigen Gene Mutation Database at NCBI, NIH
- XK+protein,+human at the U.S. National Library of Medicine Medical Subject Headings (MeSH)