Researchers have discovered that a gene that is associated with cancer causes the skin to tan and protects it from the sun's harmful rays. Scientists say the finding provides insight into the workings of the tumor suppressor gene known as p53. VOA's Jessica Berman reports.

For more than 20 years, researchers have been studying p53 because it is the tumor suppressor gene that is most often abnormal in human cancers.

But it appears p53 does more than put the breaks on abnormal cell growth.

"It's conceivably the most common action that p53 plays every time you walk out of your house in the morning," said David Fisher.

David Fisher is director of the melanoma program at the Dana Farber Cancer Institute at Harvard University in Boston. He led a team of researchers that found that when p53 is exposed to the sun's rays, the gene stimulates the production of pigment in the skin, causing it to darken. The resulting suntan protects the skin from potentially cancer-causing ultraviolet light.

"So this is not an effect that involves growth," he said. "It's not an effect that is involving the survival of the cell where p53 is induced, but rather it is an effect that is going ultimately to be communicated out of the cell and produce the pigment response in the deeper cells that are producing pigment within the skin."

By understanding the molecular underpinnings of skin pigmentation, Fisher hopes some day to be able to identify people who are at greatest risk of developing melanoma, the most deadly form of skin cancer, and repair their p53 response to ultraviolet light.

Fisher says research also shows that p53 plays a role in skin blemishes.

"Imagine if someone has a pigmented spot on their face from a young age," noted Fisher. "That can be purely cosmetic in the sense that it is annoying but not dangerous. And yet these can actually collectively have a huge impact on people's life. So, understanding where these came from, because they are incredibly common in human populations, gives us the first step toward figuring out how to get rid of them."

The study on p53 and skin pigmentation was published in the journal Cell.