Uncombable hair syndrome also known as Pili trianguli et caniculi is a rare syndrome characterized by a lack of hair control. It was first reported and described in the 70s and today only about 100 cases are known.
The disease affects approximately one in 10 million individuals worldwide. This figure is likely to be underestimated, as many people do not go to the doctor due to the absence of symptoms. The exact cause of the disease is unknown and no cure for this genetic disorder is known.
According to the GARD (Genetic and Rare Disease Information Center) it is a rare anomaly that is characterized by dry, curly, frizzy, disordered, clear hair that projects outwards and grows in different directions instead of down making it practically impossible to brush.
The disease typically manifests itself during childhood, although it can occur later in life. Its appearance is variable, from childhood to adulthood. In some cases, there is no family history of the disease.
When you finish reading this article it will make sense to you the characteristic hair of Albert Einstein, a prestigious scientist who suffered from this syndrome.
Structure of the hair shaft
It is a problem that affects the hair shaft, a structure composed of:
- The cuticle: outer part formed by flattened, keratinized cells without pigment.
- The cortex: forms most of the structure of the hair. It is responsible for providing elasticity and strength to the hair.
- The medulla: it is the inner part of the hair and has no direct relationship in the alterations of the stem.
Alterations in the stem structure can lead to this rare syndrome. It is a strong, but totally untamable hair given its characteristic structure.
If we look at a hair of a person suffering from this syndrome, the hair is triangular or heart-shaped. This alteration is clinically evident when about 50% of the hair follicles are affected.
Genetics behind Uncombable Hair Syndrome
It has recently been discovered to be caused by mutations in one of 3 genes, PADI3, TGM3 and TCHH. These three genes encode proteins involved in hair shaft formation.
The inheritance pattern appears to be autosomal recessive. However, other familial cases appear to be inherited following an autosomal dominant pattern of inheritance, and may be caused by defects in other genes that have not been identified but which are also involved in hair formation.
There are two types of this syndrome:
- Hereditary: The hereditary form affects individuals who have inherited the mutation from one of their parents.
- Acquired: it occurs in people whose family members have never suffered from this disease.