Curly Hair Gene

In a paper published in Nature Genetics, she and colleagues presented their research on the cause of a type of curly hair called wooly hair. This type of hair is not the normal curly hair seen in people of Black African ancestry but especially brittle curls that appears rarely in people of Caucasian and Asian descent. People with this disorder have hair that breaks easily and this sometimes leads to baldness.

Wooly hair tends to grow sparsely. image courtesy Dr. Angela Christiano

“It’s difficult to wash, when you try to comb it or blow dry it, or style it, it breaks off very easily, and it’s unattractive. I mean thin sparse hair—especially for women, I think—is a clinical problem," Christiano explains.

Under a microscope, splits can be seen throughout the hair fiber. Wooly hair is sometimes associated as part of other medical conditions like Naxos disease or Carvajal syndrome but the subjects in this study had only wooly hair with no other health problems.

Christiano says that this type of hair condition has been diagnosed in Europe, Brazil and Pakistan. For this study she got hair and blood samples from six families in Pakistan. The researchers did a complete analysis of the DNA and found a mutation in a gene called P2RY5.

“So for the first time, this is a gene that’s involved in hair growth and hair loss, as well as hair texture,” says Christiano.

The mutation leads to a lack of function of the cell surface protein called G protein-coupled receptor.

Because it is on the cell surface, Christiano thinks she will be able to easily develop drugs to combat wooly hair that could be applied directly to the scalp or skin.

Christiano compares this cell surface protein to a lock.

“It basically sits there waiting for a key to come along and trigger a mechanism inside the cell that will lead to the events involved in hair growth or hair loss. So in the field of drug discovery, these lock proteins are the ones that are most easily 'druggable' meaning it’s the easiest to find a suitable key to unlock their function,” she says.

But Christiano also thinks that drugs could be developed to reduce excessive hair growth. And now the fun part. She hopes to also find ways to change curly hair to straight or vice versa—not with an iron or a perm, but with drops or foam that would actually change the way your hair grows. How does Christiano feel about science being used for cosmetic purposes?

“I think in dermatology, one of the advantages of our discoveries is that they have lots of immediate clinical applications, and it would be great if all of our discoveries were used for medical conditions like medical forms of hair loss. But many times there’s immediate translation into the cosmetics arena so if people can, you know, improve their appearance using science, then I think that’s a great thing."

Although Christiano only studied the genes in a particular population she says that the results, for the first time, give insight into the genes that may control hair texture in other populations who do not have hair abnormalities.

PUBLICATION: Nature Genetics, online February 24, 2008

AUTHORS: Yutaka Shimomura, Muhammad Wajid, Yoshiyuki Ishii, Lawrence Shapiro, Lynn Petukhova, Derek Gordon & Angela M Christiano

RESEARCH FUNDED BY: National Institutes of Health and National Institute of Arthritis and Musculoskeletal and Skin Diseases