We know that those people with dark skin and dark hair have a lesser chance of developing melanoma than those with red hair and fair skin. It has been thought that people with fair skin/red hair have less natural protection from the sun’s UV rays and that is what caused the increased risk of skin cancer. Researchers at the Massachusetts General Hospital Cutaneous Biology Research Center and Cancer Center believe that is only part of the reason. A recent study they conducted may show that the type of skin pigment in those with red hair and fair skin may itself contribute to the risk of cancer.
Individuals with dark hair or skin have a type of pigment called eumelanin and those with red hair, light skin and freckles have a pigment called pheomelanin. The pigment pehomelanin is known for providing less protection against UV damage. This explains the higher risk of skin cancer in areas exposed to the sun, however, does not necessarily explain why these individuals have a higher risk of melanoma in areas of the skin that are not regularly exposed to the sun.
The recent study studied two groups of mice, one group with the dark melanin and one with the fair skin melanin. The pigment cells were activated on patches of the mice’s skin. Scientists believed that once the mice were exposed to UV rays, the mice with the fair skin melanin would develop skin cancer. However, within several months, without being exposed to UV rays, half of these mice developed melanomas. Only a few of the dark mice did.
While the research doesn’t provide any definitive answers or provide a clear path to preventing skin cancer it does provide one more clue to understanding melanoma. It also may indicate that for red hair/light skin individuals, if it is the pigment itself contributing to melanoma, protecting their skin from the sun may not be enough. Extra diligence in self-exams and seeing their doctor for any changes in their skin is extremely important. Melanoma, when identified and treated early, is almost always treatable.
"Unexpected Factor Contributes to Melanoma Risk in Red-Haired, Fair-Skinned Individuals," 2012, Oct 31, Staff Writer, Science Daily