Redheads Found to Be at Greater Risk for Skin Cancer
“Red hair, sir, in my opinion, is dangerous” said PG Wodehouse. In one sense, he may be right. Researchers have found a link between the gene that gives redheads their hair color and an increased melanoma skin cancer risk.
The melanocortin 1 receptor (MC1R) is one of the key proteins regulating skin and hair color. It works by controlling the type of melanin being produced. In the United States, about 25% of the population carries a mutation in the MC1R that causes red hair. This same mutation may also trigger a cancer-causing signaling pathway when redheads are exposed to ultraviolet (UV) radiation.
It has long been known that those with fair skin are at increased risk for melanoma. Redheads tend to have even fairer skin than blondes so therefore are at greater risk. In fact, they are 10 times more likely to develop melanoma than those without fair skin. But aside from the obvious risk of skin damage that can lead to cancer, redheads may also have a genetic reason for the increased risk.
Researchers from Beth Israel Deaconess Medical Center and Boston University School of Medicine have found that the mutation in the MC1R gene that leads to the production of the red-hair pigment known as pheomelanin also prevents it from binding properly to a gene known as PTEN which helps protect against cellular damage that promotes cancer. As a result, after exposure to UV rays, PTEN is destroyed at a higher rate and the growth of the pigment-producing cells is accelerated. In addition, the activity synchronizes with another genetic mutation (in the BRAF gene) which is found in 70% of human melanomas.
The biological pathway in which this process works is already known to be important in breast cancer, ovarian cancer and lung cancer.
Dr. Rutao Cui, of BUSM's department of dermatology, and Dr. Wenyi Wei PhD, of the Deaprtment of Pathology at BIDMC, note that the findings are still fresh and that there are “still many unknowns.” But they hope this will offer a useful starting point for further studies.
Melanoma skin cancers are not as common as basal cell skin cancer, but are more deadly. Nearly 77,000 people are expected to be diagnosed with melanoma each year and about 9.500 are expected to die from the disease.
The Skin Cancer Foundation offers the following Melanoma Prevention Guidelines:
• Seek the shade, especially between 10 AM and 4 PM.
• Do not burn.
• Avoid tanning and UV tanning booths.
• Cover up with clothing, including a broad-brimmed hat and UV-blocking sunglasses.
• Use a broad spectrum (UVA/UVB) sunscreen with an SPF of 15 or higher every day. For extended outdoor activity, use a water-resistant, broad spectrum (UVA/UVB)
sunscreen with an SPF of 30 or higher.
• Apply 1 ounce (2 tablespoons) of sunscreen to your entire body 30 minutes before going outside. Reapply every two hours or immediately after swimming or excessive sweating.
• Keep newborns out of the sun. Sunscreens should be used on babies over the age of six months.
• Examine your skin head-to-toe every month.
• See your physician every year for a professional skin exam.
Juxiang Cao, Lixin Wan, Elke Hacker et al, MC1R is a potent regulator of pten after UV exposure in melanocytes, Molecular Cell 51(4) pp. 409 - 422, published online 22 August 2013 (DOI: 10.1016/j.molcel.2013.08.010).
Skin Cancer Foundation