Soon genetic engineering may be able to reduce sunburn. A study in Nature. com says a chemical that is involved in immune system signaling might reverse some types of skin damage caused by sunlight. The chemical could reduce sunburn by activating DNA-repair mechanisms, which means it may even possibly prevent and treat skin cancer. Skin cancer is caused when ultra-violet energy damages the DNA inside cells.
Skin cancer is most common to people of Western European descent, with over one million people being inflicted yearly in the US. Researchers have found that cultured human cells treated with the protein interleukin- 12 (IL-12) were less likely to receive permanent damage (or death) after being exposed to ultraviolet light. Cells showed as much damage as normal (control) cells after being exposed, but they had less damage several hours later. This was also mirrored in mice treated with IL-12 exposed to UV rays as compared to those not treated with IL-12.
So basically, this means that it does not help block damage from UV rays, but instead repair it (contrary to sunscreen). IL-12 may become a treatment for sunburns, but it will certainly not replace sunscreen. IL-12, a protein, stimulates a cellular editing system that "snips" (no further explanation available... ) out damaged pieces of DNA from the sequence. IL-12 is not the first chemical that promotes DNA repair after UV damage.
Earlier this year (2001) a bacterial enzyme smeared on the skin acted much the dame as IL-12. The only difference is IL-12 is naturally produced in humans, and further doses are unlikely to cause allergic reactions. The bacterial enzyme is not naturally produced, and therefore is foreign to the human immune system. My guess is in the next year or so this protein will become available as a tool in emergency rooms for sunburn repair, and later out in pharmacies. If IL-12 is or can be a product smeared on skin, it may be added to existing sunscreens for a blocking and repair effect.