Meyahealth
HomeGeneticsGeneKRT12 gene
Back to Gene
KRT12 gene
Reviewed by Medicinsk Expert•Last updated: 2026-10-22•Gene

KRT12 gene

The KRT12 gene provides instructions for making keratin 12, a protein that forms the structural framework of the corneal epithelium in the eye.

Normal Function

The KRT12 gene provides instructions for making a protein called keratin 12. Keratins are a group of tough, fibrous proteins that form the structural framework of epithelial cells, which are cells that line the surfaces and cavities of the body. Keratin 12 is produced in a tissue on the surface of the eye called the corneal epithelium. This tissue forms the outermost layer of the cornea, the clear front covering of the eye, acting as a barrier to prevent foreign materials like dust and bacteria from entering.

The keratin 12 protein partners with another keratin protein, keratin 3, to form molecules known as intermediate filaments. These filaments assemble into strong networks that provide strength and resilience to the corneal epithelium.

Health Conditions Related to Genetic Changes

Meesmann corneal dystrophy

At least 20 mutations in the KRT12 gene have been found to cause Meesmann corneal dystrophy, an eye disease characterized by the formation of tiny cysts in the corneal epithelium.

Almost all of the KRT12 gene mutations associated with this condition change single amino acids in the keratin 12 protein. These changes occur in regions critical for the formation and stability of intermediate filaments. The altered keratin 12 protein interferes with the assembly of these filaments, weakening the structural framework of the corneal epithelium. As a result, the outer layer of the cornea becomes abnormally fragile and develops cysts, which likely contain clumps of abnormal keratin proteins and other cellular debris. When these cysts rupture, they cause eye irritation, increased sensitivity to light (photophobia), and related symptoms.

Other Names for This Gene

  • CK-12
  • cytokeratin-12
  • K12
  • K1C12_HUMAN
  • keratin 12, type I
  • keratin, type I cytoskeletal 12
  • keratin-12

Frequently Asked Questions

Management focuses on symptom relief: lubricating eye drops, preservative‑free artificial tears, and sometimes topical steroids for inflammation. In severe cases, a superficial keratectomy or laser ablation may be considered to remove cysts, but these procedures carry risks and are rarely needed. Regular follow‑up with an ophthalmologist is essential.
Vision loss is uncommon but can occur if cysts rupture and cause corneal scarring or if secondary infections develop. Patients should monitor for sudden changes in visual acuity, persistent redness, or increased pain, and seek prompt ophthalmologic care if these occur.
Diagnosis starts with a slit‑lamp examination that reveals characteristic epithelial cysts. If Meesmann dystrophy is suspected, a corneal biopsy or impression cytology can be performed, and DNA from the patient’s blood or saliva is sequenced for KRT12 mutations. Identifying a pathogenic variant confirms the diagnosis and informs family counseling.
Common symptoms include frequent eye irritation, gritty sensation, blurred vision, and recurrent corneal epithelial cysts that may appear as tiny white spots. If these symptoms worsen or are accompanied by redness or sensitivity to light, an eye care professional should evaluate for Meesmann dystrophy.
Source: MedlinePlus, National Library of Medicine

MedlinePlus brings together authoritative health information from the National Library of Medicine (NLM), the National Institutes of Health (NIH), and other government agencies and health-related organizations.

Meyahealth

Ⓒ 2026. All rights reserved by MEYA

About UsTerms & PolicyFAQ