A Columbia University Medical Center research team has discovered a gene involved in determining hair texture in humans. According to a report on the university Web site, the team's genetic analysis demonstrated that mutations in a gene known as P2RY5 cause hereditary "woolly hair"—hair that is coarse, dry, tightly curled and sparse.
"Our findings indicate that mutations in the P2RY5 gene cause hereditary woolly hair," said lead author Angela M. Christiano, PhD, the Richard and Mildred Rhodebeck Professor of Dermatology and Genetics & Development, at the Columbia University College of Physicians and Surgeons, in the report. "This is significant as it represents the discovery of the first new gene whose primary function seems to be the determination of hair texture in humans."
She added that this genetic finding could lead the development of new treatments for excessive or unwanted hair, or potentially for treatments to grow hair. These findings were published in an online edition of Nature Genetics on Feb. 24, 2008, and the paper will appear in the journal's March print issue.
According to the report, hair shafts emerge from the surface of the skin and display wide variability in texture and color. Since research has shown woolly hair to be common among Pakistani families, Christiano and her colleagues set out to determine why this type of hair was specific to this group of people in hopes to find the genetic basis and to learn more about the genetic underpinnings of different hair textures.
To identify a gene involved in controlling hair texture, Christiano and her team reportedly performed a genetic analysis of six families of Pakistani descent, who all shared hereditary woolly hair. The cause of hereditary woolly hair was found to be a mutation in a gene called P2RY5. Until this discovery, the pathogenesis of hereditary woolly hair had been largely unknown. The researchers proposed that mutations in P2RY5 most likely result in hair follicle disruptions that then compromise its anchoring to the hair shaft and cause the abnormal bending of the bulb region, leading to woolly hair.
Christiano's discoveries have led to the identification of several genes controlling human hair growth. It remains to be determined whether common variants on the P2RY5 gene can also contribute to naturally occurring variations in hair texture between different human populations. According to the researchers, P2RY5 is the first gene of a type known as a G-protein coupled receptor (GPCR) implicated in a human hair disorder—thereby making it possible to develop drugs that target this receptor.