Keratin 20

KRT20
Identifiers
Aliases	KRT20, CD20, CK-20, CK20, K20, KRT21, keratin 20
External IDs	OMIM: 608218; MGI: 1914059; HomoloGene: 56837; GeneCards: KRT20; OMA:KRT20 - orthologs
Gene location (Human)
Chr.	Chromosome 17 (human)
End	40,885,242 bp
Gene location (Mouse)
Chr.	Chromosome 11 (mouse)
End	99,328,976 bp
RNA expression pattern
	Top expressed in
	mucosa of transverse colon; ; rectum; ; duodenum; ; appendix; ; epithelium of colon; ; gastric mucosa; ; smooth muscle tissue; ; body of stomach; ; urinary bladder; ; muscle layer of sigmoid colon;
	Top expressed in
	intestinal villus; ; Ileal epithelium; ; large intestine; ; colon; ; duodenum; ; left colon; ; mucous cell of stomach; ; pyloric antrum; ; Paneth cell; ; jejunum;
	More reference expression data
	n/a
Gene ontology
Molecular function	structural molecule activity; protein binding; structural constituent of cytoskeleton;
Cellular component	cytoplasm; intermediate filament; cytosol;
Biological process	intermediate filament organization; apoptotic process; regulation of protein secretion; keratinization; cornification; cellular response to starvation;
	Sources:Amigo / QuickGO
Orthologs
	54474
	66809
	ENSG00000171431; ENSG00000263057
	ENSMUSG00000035775
	P35900
	Q9D312
	NM_019010
	NM_023256
	NP_061883
	NP_075745
	Wikidata
View/Edit Human	View/Edit Mouse

Keratin 20, often abbreviated CK20, is a protein that in humans is encoded by the KRT20 gene.

Keratin 20 is a type I cytokeratin. It is a major cellular protein of mature enterocytes and goblet cells and is specifically found in the gastric and intestinal mucosa.

In immunohistochemistry, antibodies to CK20 can be used to identify a range of adenocarcinoma arising from epithelia that normally contain the CK20 protein. For example, the protein is commonly found in colorectal cancer, transitional cell carcinomas and in Merkel cell carcinoma, but is absent in lung cancer, prostate cancer, and non-mucinous ovarian cancer. It is often used in combination with antibodies to CK7 to distinguish different types of glandular tumour.