Tanning Gene p53 May Increase Risk of Testicular Cancer

A recent study shows that a tanning gene could be linked to an increased risk of testicular cancer.

According to scientists from the U.S. National Institutes for Health and the University of Oxford in England, nearly 80 percent of white men are carriers for this variant of the gene.

"Gene variations occur naturally, and may become common in a population if they convey a health benefit," Douglas Bell, Ph.D., author on the paper and researcher at the National Institute of Environmental Health Sciences (NIEHS), part of NIH said, via a press release. "It appears that this particular variant could help protect light-skinned individuals from UV skin damage, like burning or cancer, by promoting the tanning process, but it permits testicular stem cells to grow in the presence of DNA damage, when they are supposed to stop growing."

Bell and colleagues examined the p53 gene that stimulates skin tanning when ultraviolet light activates it via the skin. It must bind with a specific sequence of DNA that's located in a gene known as the KIT ligand oncogene that stimulates melanocyte production and causes the skin to tan.

Study authors selected possible leads from an intersection of over 20,000 p53 binding sites in the human genome and more than 10 million inherited genetic variations that were genotyped in the 1000 Genomes Project and 62,000 genetic variations associated with human cancers identified in genome-wide association studies.

"In the end, one variant in the p53 pathway was strongly associated with testicular cancer, but also, surprisingly, displayed a positive benefit that is probably related to tanning that has occurred as humans evolved," researchers noted, via the release. 

More information regarding the study can be found via the journal Cell.