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The official name of this gene is “TEK tyrosine kinase, endothelial.”
TEK is the gene's official symbol. The TEK gene is also known by other names, listed below.
The TEK gene (also called the TIE2 gene) provides instructions for making a protein called TEK receptor tyrosine kinase. The TEK receptor tyrosine kinase (or TEK receptor) is active (expressed) mainly in endothelial cells, which line the walls of blood vessels. When the TEK receptor is activated, it triggers a series of chemical signals that facilitates communication between endothelial cells and smooth muscle cells. Layers of smooth muscle cells surround layers of endothelial cells lining the walls of blood vessels. Communication between these two cell types is necessary to direct blood vessel formation (angiogenesis) and ensure the structure and integrity of blood vessels.
The TEK receptor is also found in bone marrow, where it is expressed in blood-forming cells called hematopoietic stem cells. The role of the TEK receptor in hematopoietic stem cells is unknown. Researchers speculate that the TEK receptor aids in hematopoietic stem cell growth and division (proliferation) or cell specialization (differentiation).
The TEK gene belongs to a family of genes called fibronectin type III domain containing (fibronectin type III domain containing). It also belongs to a family of genes called immunoglobulin superfamily, immunoglobulin-like domain containing (immunoglobulin superfamily, immunoglobulin-like domain containing).
A gene family is a group of genes that share important characteristics. Classifying individual genes into families helps researchers describe how genes are related to each other. For more information, see What are gene families? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genefamilies) in the Handbook.
At least eight mutations in the TEK gene have been found to cause multiple cutaneous and mucosal venous malformations (also known as VMCM). These mutations change single protein building blocks (amino acids) in the TEK receptor tyrosine kinase. The most common mutation replaces the amino acid arginine with the amino acid tryptophan at position 849 in the TEK receptor (written as Arg849Trp or R849W). The R849W mutation and most of the others that cause this condition result in a TEK receptor that is always turned on (overactive).
An overactive TEK receptor is thought to disrupt the communication between endothelial cells and smooth muscle cells. It is unclear how a lack of communication between these cells causes venous malformations. These abnormal blood vessels show a deficiency of smooth muscle cells while endothelial cells are maintained. Venous malformations cause lesions below the surface of the skin or mucous membranes, which are characteristic of VMCM.
Cytogenetic Location: 9p21
Molecular Location on chromosome 9: base pairs 27,109,148 to 27,230,173
The TEK gene is located on the short (p) arm of chromosome 9 at position 21.
More precisely, the TEK gene is located from base pair 27,109,148 to base pair 27,230,173 on chromosome 9.
See How do geneticists indicate the location of a gene? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genelocation) in the Handbook.
You and your healthcare professional may find the following resources about TEK helpful.
You may also be interested in these resources, which are designed for genetics professionals and researchers.
See How are genetic conditions and genes named? (http://ghr.nlm.nih.gov/handbook/mutationsanddisorders/naming) in the Handbook.
acids ; amino acid ; angiogenesis ; arginine ; bone marrow ; cell ; cutaneous ; deficiency ; differentiation ; endothelial cells ; expressed ; gene ; hematopoietic ; kinase ; mucous ; muscle cells ; mutation ; precursor ; proliferation ; protein ; receptor ; soluble ; stem cells ; tryptophan ; tyrosine
You may find definitions for these and many other terms in the Genetics Home Reference Glossary (http://ghr.nlm.nih.gov/glossary).
The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? (http://ghr.nlm.nih.gov/handbook/consult/findingprofessional) in the Handbook.