Variations in genes that control the color of our skin, hair and eyes can raise the risk of deadly tumors, scientists from DeCode Genetics Inc and Australia said, Bloomberg reported.
Studies published today in the journal Nature Genetics linked common versions of pigment genes to cutaneous melanoma, which causes the majority of about 8,000 US skin cancer deaths a year, as well as less deadly tumors.
Skin cancer is the most common US malignancy. It's been long known that people with fair skin have a higher chance of getting tumors than those with darker complexions. The study suggests gene testing would more precisely determine individual risk, and identifies a molecular process that may be targeted as a therapy, said DeCode Chief Executive Officer Kari Stefansson.
``This is a clear example of the interplay between genes and the environment,'' Stefansson said in a telephone interview. ``If you have this mutation, you definitely should not sunbathe very much.''
About 62,000 of more than 1 million cases of skin cancer diagnosed this year will be melanoma, according to the National Cancer Institute. A test for the gene variant will be added to DecodeMe, the company's service that uses DNA analysis to help individuals determine health risks and their ethnic origins.
DeCode gained 1 cent to $1.61 May 16 in Nasdaq Stock Market composite trading, after losing 53 percent over the past 12 months.
DNA is the body's code for making proteins and controlling cell growth. DeCode has been a leader in finding small variations, called ``snips,'' in the DNA code that in some cases may raise the risk of conditions such as heart attacks, diabetes, and eye disease.
A snip in another gene involved in pigmentation, called MC1R, has also been implicated in skin cancer. When DeCode looked at 11 more pigment-associated genes they found variations in three that raise the risk of skin cancer by more than double.
The strongest association was in a variation of a gene called ASIP that, like MC1R, contributes to the production of light pigment that contributes to fair skin and red hair.
``They may have opened up a away of looking at skin pigmentation and cancer that hadn't been uncovered,'' said Hensin Tsao, a Harvard Medical School geneticist and dermatologist at Massachusetts General Hospital in Boston, in a telephone interview. ``These genes may not be targets for new drugs against metastatic melanoma, but they may help us find better ways of preventing skin cancer.''
DeCode's study looked at DNA data from more than 70,000 people with and without cancer to find the link. A separate study led by Kevin Brown, a geneticist at the Queensland Institute of Biomedical Research in Brisbane, Australia, also implicated a variation in the ASIP gene in skin cancer.