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 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% of mice without red fur contracted
"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,"
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 emphasise 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.
"Redheads should get more frequent body checks," said Downie, a dermatologist
based in Montclair, NJ.
"If they have no family history of skin cancer, they should still be checked
at least twice a year, rather than the annual check we recommend for everyone
else. If they have a family history of skin cancer, they should be checked every
This is crucial since melanoma could form even on a part of the body that is
never touched by sunlight.
"The location on one's skin of where a melanoma may occur is not necessarily
confined to the sun-exposed parts of the skin," Fisher said. "It could occur
elsewhere on the body."
Redheads also should practice vigilant sun avoidance, Downie said. They
should use a sunscreen with at least SPF 30, and they should reapply it every
They also should consider wearing broad-brimmed hats when outdoors, sticking
to the shady side of the sidewalk and even vacationing in mountain areas rather
than at the beach.
"Unfortunately with redheads, they have to practice some lifestyle
alterations," Downie said. "They should practice even more strict sun avoidance
than we originally thought they should."
Visit the US Centers for Disease Control and Prevention for tips on skin
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