"So it made sense that changing its activity could affect hair or skin colour," researchers said.
Catherine Guenther, an HHMI research specialist in Kingsley's lab, began experiments to search for regulatory switches that might specifically control hair colour.
"When we found the hair follicle switch, we could then ask what is different between blondes and brunettes in northern Europe," Kingsley said.
Examining the DNA in that regulatory segment, they found a single letter of genetic code that differed between individuals with different hair colours.
"Given Kit ligand's range of activities throughout the body, many such regulatory elements are likely scattered throughout the DNA that surrounds the gene. We think the genome is littered with switches," Kingsley emphasised.
