Rare Oncology News

Disease Profile

Uncombable hair syndrome

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.


US Estimated

Europe Estimated

Age of onset






Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Pili trianguli et Canaliculi; Cheveux incoiffables; Unmanageable hair syndrome;


Congenital and Genetic Diseases; Skin Diseases


Uncombable hair syndrome (UHS) is a rare disorder of the hair shaft of the scalp. It is usually characterized by silvery-blond or straw-colored hair that is disorderly; stands out from the scalp; and cannot be combed flat. It may first become apparent from 3 months of age to 12 years of age.[1] Most cases are isolated, but in some cases it has been described in association with other diseases, such as ectodermal dysplasias, Bork syndrome and Angel-shaped phalangoepiphyseal dysplasia. The syndrome has been found to be caused by mutations in the genes PADI3, TGM3, and TCHH. These three genes code for proteins that are involved in hair shaft formation.[2] The syndrome appears to be inherited in an autosomal recessive fashion; however, cases inherited in an autosomal dominant manner may also exist, as there are other genes involved in hair formation. The condition often spontaneously regresses in late childhood.[3] Some published studies suggest that biotin may improve the condition.[4]


Uncombable hair syndrome (UHS) may first become apparent any time between the ages of 3 months and 12 years.[3] It only affects the scalp hair. The quantity of hair remains normal, but the hair often grows slowly.[5] Over time the hair becomes progressively silvery-blond or straw-colored; dry and disordered (standing out and growing in different directions); and unmanageable to comb flat.[3] In some cases, constant efforts to groom the hair lead to breakage, but increased fragility is not a constant feature of the condition. In later childhood, there is usually a considerable amount of spontaneous improvement.[1][6]

In cases where UHS is part of a syndrome, there may be other signs and symptoms present; therefore, it is important to determine whether the UHS is isolated or syndromic.

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
80%-99% of people have these symptoms
Coarse hair
Coarse hair texture
White hair
Woolly hair
Kinked hair
5%-29% of people have these symptoms
Patchy alopecia
Patchy baldness
Percent of people who have these symptoms is not available through HPO
Autosomal recessive inheritance
Dry hair
Pili canaliculi
Uncombable hair


Three genes have been associated with uncombable hair syndrome (UHS): PADI3, TGM3, and TCHH. These three genes code for proteins responsible for the formation of the hair shaft. In these cases, the mode of inheritance appears to be autosomal recessive. Nonetheless, other cases in which multiple family members have the condition seem to be inherited in an autosomal dominant fashion and may be caused by other genes that have yet to be identified. In the majority of cases, UHS is isolated and is not part of a syndrome. The syndromic forms of UHS are caused by other genes. 


A diagnosis of uncombable hair syndrome (UHS) is made by observing the characteristic symptoms of the condition, as well observing the hair shaft under a special microscope.[3] When the individual hair strands are viewed under a microscope, the hair is either triangular or kidney-shaped on cross section, and has a canal-like longitudinal groove along one or two faces.[7][1] People with concerns about symptoms of UHS are encouraged to speak with their dermatologist about being evaluated for this condition. The recent discovery of the genes associated with the condition may lead to genetic testing in the future. 

Testing Resources

  • Orphanet lists international laboratories offering diagnostic testing for this condition.


    There is no definitive treatment for uncombable hair syndrome, but the condition usually improves or resolves on its own with the onset of puberty. Gentle hair care is generally recommended using conditioners and soft brushes, along with avoiding harsh hair treatments such as permanent waves (perms); chemical relaxants; or excessive brushing and blow drying. These strategies may improve the general manageability of the hair, although how well they work is subjective.[6]

    Another strategy that has been suggested to improve the appearance of the hair is the use of biotin supplements. One case report suggested significant improvement in hair strength and combability, with an increase in rate of growth after 4 months of supplementation.[6]


    Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

    Organizations Supporting this Disease

      Learn more

      These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

      Where to Start

      • DermNet NZ is an online resource about skin diseases developed by the New Zealand Dermatological Society Incorporated. DermNet NZ provides information about this condition.
      • Genetics Home Reference (GHR) contains information on Uncombable hair syndrome. This website is maintained by the National Library of Medicine.

        In-Depth Information

        • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
        • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
        • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
        • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
        • PubMed is a searchable database of medical literature and lists journal articles that discuss Uncombable hair syndrome. Click on the link to view a sample search on this topic.


          1. Ralph Trüeb. Uncombable hair syndrome. Orphanet Encyclopedia. September 2003; https://www.orpha.net/data/patho/GB/uk-uncombable.pdf.
          2. Basmanav, FBÜ & cols. Mutations in Three Genes Encoding Proteins Involved in Hair Shaft Formation Cause Uncombable Hair Syndrome. The American Journal of Human Genetics. 2016; 99(6):1292-1304. https://www.cell.com/ajhg/abstract/S0002-9297(16)30440-2.
          3. Alexander Navarini. Uncombable hair syndrome. Orphanet. January, 2012; https://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=en&Expert=1410.
          4. Boccaletti V, Zendri E, Giordano G, Gnetti L, De Panfilis G. Familial Uncombable Hair Syndrome: Ultrastructural Hair Study and Response of Biotin. Pediatr Dermatol. 2007;
          5. Rieubland C, de Viragh PA & Addor MC. Uncombable hair syndrome: a clinical report. Eur J Med Genet. 2007 Jul-Aug; https://www.ncbi.nlm.nih.gov/pubmed/17526443.
          6. Calderon P, Otberg N, Shapiro J. Uncombable hair syndrome. J Am Acad Dermatol. September, 2009; 61(3):512-515. https://www.ncbi.nlm.nih.gov/pubmed/19700017.
          7. Jarell AD, Hall MA, Sperling LC. Uncombable hair syndrome. Pediatr Dermatol. 2007 Jul-Aug; 24(4):436-438. https://www.ncbi.nlm.nih.gov/pubmed/17845183.
          8. Carol A. Bocchini. Uncombable hair syndrome. OMIM. April 5, 2011; https://www.omim.org/entry/191480.

          Rare Oncology News

          fascinating Rare disease knowledge right in your inbox
          Subscribe to receive