Meyahealth
HomeGeneticsGenePAX6 gene
Back to Gene
PAX6 gene
Reviewed by Medicinsk Expert•Last updated: 2026-10-22•Gene

PAX6 gene

The PAX6 gene provides instructions for making a protein that acts as a transcription factor, playing a critical role in the development of the eyes, brain, spinal cord, and pancreas.

Normal Function

The PAX6 gene belongs to a family of genes that play a critical role in the formation of tissues and organs before birth. PAX genes are also important for the normal function of certain cells after birth. To carry out these roles, the PAX genes provide instructions for making proteins that bind to specific areas of DNA and help control the activity (expression) of particular genes. Proteins that perform this role are called transcription factors.

Before birth, the PAX6 protein regulates genes involved in the formation of the eyes, the brain and spinal cord (central nervous system), and the pancreas. Within the brain, the PAX6 protein is involved in the development of a specialized group of cells that process smell (the olfactory bulb). Additionally, the PAX6 protein controls many aspects of eye development. After birth, the PAX6 protein is found in many different eye structures where it regulates gene activity.

Health Conditions Related to Genetic Changes

Aniridia

Genetic changes that cause disease are called pathogenic variants. Hundreds of pathogenic variants in the PAX6 gene have been found to cause aniridia. People with this condition have a partial or complete absence of the colored part of the eye (the iris) along with associated vision problems. Most of the pathogenic variants that cause aniridia create a premature stop signal in the instructions for making the PAX6 protein, leading to an abnormally short, nonfunctional protein. Without enough functional PAX6 proteins, the formation of the eyes is disrupted before birth.

Coloboma

Pathogenic variants in the PAX6 gene can cause coloboma, in which there is a gap or split in one of the structures that make up the eye. Most of these variants lead to the substitution of one amino acid for another in the PAX6 protein, which reduces but does not eliminate the protein's ability to function as a transcription factor.

Peters anomaly

Peters anomaly is characterized by the abnormal development of certain structures at the front of the eye and the clouding of the cornea. Variants in the PAX6 gene reduce the protein's ability to bind to DNA, disrupting its role as a transcription factor and impairing normal eye development.

WAGR syndrome

The PAX6 gene is located in a region of chromosome 11 that is deleted in people with WAGR syndrome. This syndrome is named for its main features:

  • Wilms tumor (a childhood kidney cancer)
  • Aniridia
  • Genitourinary anomalies
  • Range of developmental delays

Affected individuals are missing one copy of the PAX6 gene in each cell, which is associated with the characteristic eye features of the syndrome and may affect brain development.

Other disorders

Pathogenic variants in the PAX6 gene can cause additional eye problems, including:

  • Ectopia pupillae (pupils not centrally positioned)
  • Optic nerve hypoplasia (underdevelopment of structures carrying information from eyes to brain)
  • Fovea hypoplasia (underdevelopment of the region at the back of the eye responsible for clear vision)
  • Cataracts (clouding of the lenses)
  • Nystagmus (involuntary eye movements)
  • Keratitis (inflammation of the cornea)

Frequently Asked Questions

dults with PAX6 mutations should have yearly comprehensive eye exams that check for: (1) cataract formation, especially posterior subcapsular cataracts; (2) glaucoma due to angle‑structure abnormalities; (3) keratopathy from exposure because of a small or absent iris; and (4) retinal changes that can affect peripheral vision. Early detection allows timely treatment to preserve vision.
niridia caused by PAX6 pathogenic variants is usually autosomal dominant, meaning each child has a 50 % chance of inheriting the altered gene. If the variant is a new (de novo) mutation in you, the risk to siblings is low, but your own children remain at 50 % risk. Genetic counseling and targeted testing can clarify the exact inheritance pattern for your family.
clinical laboratory will perform sequencing of the PAX6 coding regions (often via next‑generation sequencing) and may also assess for deletions/duplications using copy‑number analysis. No special preparation is required—usually a blood sample is drawn. Bring any prior eye‑exam reports and a list of family members with eye anomalies to help the clinician interpret results.
Yes. Wear UV‑blocking sunglasses and a wide‑brimmed hat to reduce photophobia and cataract risk. Use lubricating eye drops or ointments to prevent corneal drying, especially in dry environments. Avoid smoking, which accelerates cataract and retinal degeneration. If you have light‑sensitivity, consider tinted lenses prescribed by your eye‑care provider. Regular follow‑up with a low‑vision specialist can also provide adaptive devices to maximize functional vision.
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