You’re late for work, in a rush, and your child’s hair just won’t cooperate. It could be in their genes, a new study suggests.
A team at the University of Bonn in Germany found mutations in three genes that lead to “uncombable hair.” In most cases, those affected are children with extremely frizzy, dry and generally light blonde hair with a characteristic shine.
The symptoms don’t usually last through adulthood, and the condition itself is considered to be rare. It was first described in specialist literature in 1973, and since then about 100 cases have been recorded worldwide. Regina Betz, a professor from the Institute for Human Genetics at the University of Bonn, said just because the condition is rare doesn’t mean people don’t have the uncombable hair gene.
“We assume that there are much more people affected,” Betz said in a press release. “Those who suffer from uncombable hair do not necessarily seek help for this from a doctor or hospital.”
As a specialist for rare hereditary hair disorders, Betz was introduced to a family with two children who had uncombable hair through a British colleague. Through contact with her colleagues around the world, Betz said the team was able to find nine more children who had the same hair symptoms.
After finding the children, researchers sequenced the genes of the affected and found mutations in three genes involved with forming hair. Three identifiers known as PADI3, TGM3 and TCHH were found.
All of the children carried homozygous or compound heterozygous mutations in the three genes, suggesting a recessive inheritance pattern in the majority of the subjects.
PADI3 and TGM3 contain assembly instructions for enzymes. TCHH contains a protein for the hair shaft. In healthy hair, TCHH proteins join to each other with fine strands of keratin, which are responsible for hair shape and structure. Fitnat Buket Basmanav Ünalan, lead author of the study, said the first two identifiers play an important role in hair structure.
“PADI3 changes the hair shaft protein TCHH in such a way that the keratin filaments can adhere to it,” Ünalan said. “The TGM3 enzyme then produces the actual link.”
After conducting experiments in cell cultures with colleagues from the University of Toulouse in France, researchers were able to show the importance of the identified mutations in protein function. If just one of the three components isn’t functional, the structure and stability of the hair is fundamentally affected.
“From the mutations found, a huge amount can be learned about the mechanisms involved in forming healthy hair, and why disorders sometimes occur,” Betz said. “At the same time, we can now secure the clinical diagnosis of ‘uncombable hair’ with molecular genetic methods.”
While uncombable hair may be annoying and cause mental stress, it generally does not occur alongside any other health impairments, Betz said.
The syndrome is known as “Struwwelpeter” in German, or Shock-headed Peter syndrome. Shock-headed Peter, who never brushed his hair or cut his nails, is a character from a popular German children’s book, “Der Struwwelpeter” by Heinrich Hoffmann. The book is a series of morality tales that depict the horrific fate of children who commit “sins” such as thumb-sucking or playing with matches.
The study was published in the American Journal of Human Genetics.