XK (protein) explained

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]

Function

XK is a membrane transport protein of unknown action.^[4]

External links

• GeneReviews/NCBI/NIH/UW entry on McLeod Neuroacanthocytosis Syndrome
• XK at BGMUT Blood Group Antigen Gene Mutation Database at NCBI, NIH

Notes and References

1. Arnaud L, Salachas F, Lucien N, etal . Identification and characterization of a novel XK splice site mutation in a patient with McLeod syndrome . Transfusion . 49 . 3 . 479–84 . March 2009 . 19040496 . 10.1111/j.1537-2995.2008.02003.x . 27198922 .
2. Malandrini . A . Fabrizi . GM . Truschi . F . Di Pietro . G . Moschini . F . Bartalucci . P . Berti . G . Salvadori . C . Bucalossi . A . 8 . 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 . 1994 . 7931427 . 10.1016/0022-510X(94)90016-7 . 27859436 .
3. Ho . MF . Monaco . AP . Blonden . LA . Van Ommen . GJ . Affara . NA . Ferguson-Smith . MA . Lehrach . H . Fine mapping of the McLeod locus (XK) to a 150-380-kb region in Xp21 . American Journal of Human Genetics . 50 . 2 . 317–30 . 1992 . 1734714 . 1682457 .
4. Jung . HH . Russo . D . Redman . C . Brandner . S . Kell and XK immunohistochemistry in McLeod myopathy . Muscle & Nerve . 24 . 10 . 1346–51 . 2001 . 11562915 . 10.1002/mus.1154 . 44749645 .