Pili trianguli et canaliculi, also known as uncombable hair syndrome or “uncombable hair syndrome”, is a rare genetic disorder characterized by dry, frizzy, dull and often light blonde hair that is almost impossible to comb. Under the microscope, the hairs show a characteristic triangular or heart-shaped shape (pili trianguli) and a longitudinal groove structure (canaliculi), which distinguishes them from normal, round hair shafts.
The syndrome is caused by mutations in certain genes important for hair structure and development. It can be inherited in an autosomal dominant manner, meaning only one parent needs to carry the mutated gene to pass the condition on to the child. Research has linked mutations in several genes to the syndrome, including TCHH, PADI3 and TGM3, all of which play a role in the formation of hair structure.
Diagnosis is usually based on clinical assessment of hair texture, family history, and sometimes microscopic examination of the hair, which has the characteristic shape and structure. Genetic testing can also help confirm the diagnosis.
There is no specific cure for uncombable hair syndrome, but management focuses on hair care and handling to minimize discomfort:
For many sufferers, the condition of the hair improves with age, and in some cases the hair may become damaged puberty or normalize in early adulthood. Although uncombable hair syndrome can pose a challenge in daily life, it has no impact on overall health.
