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This biomarker is also known as:
  • K1CS,
  • Cytokeratin-19,
  • K19,
  • Cytokeratin 19,
  • 40-kDa keratin intermediate filament,
  • cytokeratin 19,
  • Keratin-19,
  • CK19,
  • keratin 19,
  • CK-19,
  • keratin, type I, 40-kd,
  • MGC15366,
  • keratin, type I cytoskeletal 19,


KRT19, a member of the keratin family which exists as a heterotetramer of two type I and two type II keratins, is involved in the organization of myofibers. Together with KRT8, KRT19 helps to link the contractile apparatus to dystrophin at the costameres of striated muscle. KRT18 is expressed in a defined zone of basal keratinocytes in the deep outer root sheath of hair follicles. It is also observed in sweat gland and mammary gland ductal and secretory cells, bile ducts, gastrointestinal tract, bladder urothelium, oral epithelia, esophagus, ectocervical epithelium (at protein level). It is expressed in epidermal basal cells and in nipple epidermis. It is also evident in a subset of vascular wall cells in both the veins and artery of human umbilical cord, and in umbilical cord vascular smooth muscle, as well as in muscle fibers accumulating in the costameres of myoplasm at the sarcolemma in structures that contain dystrophin and spectrin.


QA State: Curated
Type: Protein
Short Name:
HGNC Name: KRT19


There are no datasets associated with this biomarker.


The following organs have data associated with this biomarker…



Phase: Two
QA State: Curated


KRT19 (keratin 19) has been shown to be a helpful biomarker in differentiating procarcinoma from squamous cell carcinoma when screened as part of a panel including keratin 7 (KRT7), keratin 19 and nestin (NES). An assay composed of KRT19, KRT8, and KRT18 has been used to detect, measure, and evaluate circulating tumor cells (CTCs) in the blood of healthy and metastatic patients.

Performance Comment

Despite many promising new markers for ovarian cancer, CA125 remains the single best biomarker in the phase II and phase III specimens tested in this study.



Phase: One
QA State: Under Review


Performance Comment


This biomarker is currently being annotated or is under review. You must be logged in or do not have permission to view any additional information. Contact Heather Kincaid at if you should have access to this biomarker.


External Resources for KRT19

The protein encoded by this gene is a member of the keratin family. The keratins are intermediate filament proteins responsible for the structural integrity of epithelial cells and are subdivided into cytokeratins and hair keratins. The type I cytokeratins consist of acidic proteins which are arranged in pairs of heterotypic keratin chains. Unlike its related family members, this smallest known acidic cytokeratin is not paired with a basic cytokeratin in epithelial cells. It is specifically expressed in the periderm, the transiently superficial layer that envelopes the developing epidermis. The type I cytokeratins are clustered in a region of chromosome 17q12-q21.




No other associated resources found.


Mutation Statistics

Gene Name: KRT19
UniProt Accession #: P08727
Mutated Sites Count: 48
Associated Pubmed ID Count 11
CancerDO Count 22
Affected Protein Function Sites Count: 1

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