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. 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. 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. Some published studies suggest that biotin may improve the condition.
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.
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. 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.