Meyahealth
HomeGeneticsGenePADI3 gene
Back to Gene
PADI3 gene
Reviewed by Medicinsk Expert•Last updated: 2026-10-22•Gene

PADI3 gene

The PADI3 gene provides instructions for an enzyme that modifies proteins in the skin and hair follicles, which is essential for normal hair structure.

Normal Function

The PADI3 gene provides instructions for making an enzyme called peptidylarginine deiminase type III. This enzyme modifies proteins by changing the amino acid arginine to the amino acid citrulline in the presence of calcium ions, a process called deimination.

This enzyme is found in the skin's outer surface (the stratum corneum) within cells called keratinocytes. It also functions in hair follicles, where it modifies proteins involved in giving structure to the hair shaft.

Health Conditions Related to Genetic Changes

Uncombable hair syndrome

At least nine mutations in the PADI3 gene have been found to cause uncombable hair syndrome, a condition characterized by dry, frizzy, blond scalp hair that cannot be combed flat.

  • Mutations result in an enzyme with little or no activity, preventing the deimination of a protein within the hair shaft called trichohyalin.
  • Trichohyalin requires this modification to bind to other proteins and provide the hair shaft with its cylindrical shape.
  • Without this modification, the cross-section of the hair shaft becomes triangular, heart-like, or flat, resulting in the frizzy texture typical of the syndrome.
  • The condition usually improves over time, and by adolescence, hair often lies flat with a normal or nearly normal texture.

Other Names for This Gene

  • PAD3
  • PDI3
  • peptidyl arginine deiminase, type III
  • peptidylarginine deiminase III
  • protein-arginine deiminase type III
  • protein-arginine deiminase type-3

Frequently Asked Questions

Currently, no specific pharmacologic therapy exists to boost PADI3 activity. Management focuses on supportive hair care. Research into enzyme replacement or small‑molecule modulators is ongoing, but at present, the condition is managed conservatively, and most patients outgrow the hair abnormalities.
Genetic testing for PADI3 is usually done with a blood sample or cheek swab and analyzed by sequencing the gene to look for known pathogenic variants. Testing can confirm the diagnosis, help differentiate from other hair disorders, and provide information for family planning. It is typically ordered by a dermatologist or clinical geneticist after a clinical evaluation suggests the syndrome.
Uncombable hair syndrome is inherited in an autosomal recessive pattern, meaning a child must inherit two pathogenic PADI3 variants (one from each parent) to manifest the condition. Heterozygous carriers (one mutated copy) typically have normal hair and no symptoms, though rare milder hair texture changes have been reported but are not clinically significant.
Most children with uncombable hair syndrome experience gradual improvement, often by adolescence, as hair texture normalizes. Specific treatment is usually unnecessary; gentle hair care (mild shampoos, avoiding harsh chemicals, using soft brushes) can reduce breakage. Routine monitoring is only needed if there are associated skin issues or if the hair remains severely frizzy and prone to damage.
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