The risk of skin cancer is higher for redheads and sun exposure doesn't make much of a difference, says a new study.
People with fair, freckled skin and red hair produce a different kind of melanin than people who have darker skin. The difference is caused due to a mutation in the gene MC1R. The resulting pigment called pheomelanin is less effective in protecting the skin from the harmful UV radiation than eumelanin - the kind of melanin found in the darker skin.
"There is something about the redhead genetic background that is behaving in a carcinogenic fashion, independent of UV. It means that shielding from UV would not be enough," said lead author David Fisher, a cancer biologist at Massachusetts General Hospital in Boston.
For the study, sets of mice were tested for development of skin cancer. All mice were identical except for the gene that's associated with melanoma production. The genetically altered mice were also equally more susceptible for developing skin cancer.
Researchers found that mice that had the redhead pigment were more likely to develop skin cancer than dark-skin mice.
There was also a third group of mice in the study - the albino redhead - that didn't produce any pigment. Researchers found that these mice didn't develop skin cancer.
"There's no doubt that the majority of melanomas are caused by UV radiation from the sun - and protecting your skin in the sun is crucial - but this work suggests that there may be other paths to melanoma in red-haired, freckly people," said Julia Newton-Bishop, from the Cancer Research UK Centre at the University of Leeds.
According to estimates from National Cancer Institute, more than 76,000 new cases will be reported this year and more than 9,000 people will die from the cancer in the U.S.
Melanoma occurs as a mole on skin but can also occur in the eye or intestines, says NCI.
"The risk for people with this skin type has not changed, but now we know that blocking UV radiation - which continues to be essential - may not be enough," said Dr David Fisher, from Massachusetts General Hospital.