Red Hair Pigment Might Raise Melanoma Risk: Study
Dermatologists say redheads must take extra care to check skin, avoid sun
WebMD News Archive
By Dennis Thompson
THURSDAY, May 9 (HealthDay News) -- The red in redheads' hair is thought to put them at increased risk of the dangerous skin cancer melanoma, even if they don't spend a lot of time in the sun, according to a new study.
Study co-author Dr. David Fisher and his research team first uncovered the apparent link between red hair pigment and melanoma last fall. That study used genetically altered mice that had been given a mutant gene that increased their risk of contracting the skin cancer.
Now the researchers are taking the next step: asking why the body's creation of the red hair pigment -- called pheomelanin -- might prompt that risk.
Their new paper, published May 9 in the journal BioEssays, speculates that pheomelanin could increase skin cancer risk by leaving skin cells more vulnerable to DNA damage.
By determining the way pheomelanin increases cancer risk, the researchers hope to figure out a way to prevent future cases of melanoma.
"We are focusing on what the possibilities are, what the directions for new research are and how that could impact treatment," said Fisher, chief of dermatology at Massachusetts General Hospital in Boston.
The researchers had previously found that at least half of red-furred mice developed melanoma, even though none of them had been exposed to any ultraviolet (UV) radiation. By comparison, only about 10 percent of mice without red fur contracted melanoma.
"In the mouse studies, it was possible to completely remove UV and there was still a major incidence of melanoma that was attributable to the red pigment," Fisher said.
Scientists note, however, that animal studies often fail to produce similar results in humans.
Fisher speculated on two ways the red pigment might cause skin cells to be more vulnerable to melanoma.
It could be that the creation of pheomelanin in the body might also generate unstable oxygen-containing molecules that can damage cells. These molecules are known as reactive oxygen species, or ROS.
On the other hand, synthesis of pheomelanin might rob skin cells of crucial stores of antioxidants that would otherwise be used to prevent ROS damage.
"We think a new prevention opportunity exists if we can block the form of reactive oxygen damage that the red pigment is producing," Fisher said.
Despite his research, Fisher does not downplay the role that UV rays have in skin cancer risk for everyone -- particularly redheads.
"I want to emphasize that we strongly believe UV is a contributor to melanoma, and UV may actually amplify this red pigment phenomenon," he said. "It still is absolutely crucial for people to avoid sun exposure."
But the knowledge that sun exposure is only one factor in their increased risk of melanoma should prompt redheads to take additional precautions, said Dr. Jeanine Downie, a spokeswoman for the Skin Cancer Foundation.