It is known that sunburn is caused by exposure to the Sun's ultraviolet radiation that causes a reddish skin and pain. Did you know what caused the sunburn?

In the latest developments of their research, scientists at the University of California - San Diego have now found out what exactly the sunburn occurs. The researchers examined human skin cells and a mouse and found that the sunburn is caused by RNA damage.

When the body is overexposed to ultraviolet radiation (UV rays) from the Sun's rays, it causes sunburns. The UV rays affect the human skin cells' RNA molecules. RNA called as ribonucleic acid is similar to DNA but have different structural details.

When the sun-damaged cells throws out the non-coding micro-RNA (it does not make proteins on its own in the cell) present inside them, it incites other neighboring cells to start spreading the inflammatory molecules such as cytokines to the skin, thus causing a sunburn, reports LiveScience.

Cytokines are protein molecules of various types that are secretly stored by the cells of the immune system. When cytokine is released, it causes inflammation as the first response of the immune system to destroy the damaged cells after which the damaged skin starts to heal.

Damaged cells can have major effects on the human body. They can also lead to skin cancer. Scientists believe the findings can help in treating patients who are sensitive to Sun. Now that the cause of sunburn is known, they hope to stop this process.

"For example, diseases like psoriasis are treated by UV light, but a big side effect is that this treatment increases the risk of skin cancer," LiveScience quoted principal investigator Richard L. Gallo, professor of medicine at UC San Diego School of Medicine and Veterans Affairs San Diego Healthcare System as saying.

"Our discovery suggests a way to get the beneficial effects of UV therapy without actually exposing our patients to the harmful UV light. Also, some people have excess sensitivity to UV light, patients with lupus, for example. we are exploring if we can help them by blocking the pathway we discovered," he said.

Gallo and Jamie J. Bernard, who is currently working at the Susan Lehman Cullman Laboratory for Cancer Research Rutgers University, are the primary authors of the study.

The study is published in the Advance Online Publication of Nature Medicine.