Uncombable hair syndrome

Uncombable hair syndrome, abbreviated UHS, is a rare structural anomaly of the hair with a variable degree of effect, characterized by hair that is silvery, dry, frizzy, wiry and impossible to comb. It was first documented in the early twentieth century and is also known by the Latin term pili trianguli et canaliculi, the French phrase cheveux incoiffables, and the colloquial name spun-glass hair. The condition is believed to be predominantly inherited through autosomal recessive patterns, though a small number of cases show autosomal dominant transmission. Three genes have been associated with the syndrome, PADI3, TGM3 and TCHH, all coding for proteins essential to proper hair shaft development. Symptoms typically appear between three months and twelve years of age, and the syndrome affects only scalp hair structure, not the quantity or appearance of body hair elsewhere. Clinical diagnosis requires that at least fifty percent of scalp hair shafts show the characteristic abnormalities.