Just in time for the end of summer, researchers at the Yale School of Public Health are hoping to draw attention to a less studied addiction — tanning dependence.

The study investigated the possible genetic causes of tanning dependence, or an addiction to tanning despite negative health consequences. After analyzing over 300,000 genetic variants across 292 subjects, researchers found that the presence of certain variants of the Patched Domain Containing 2 gene (PTCHD2) was associated with being two thirds less likely to have an addiction to tanning. PTCHD2 is primarily expressed in the brain, although its exact biological function is unknown.

“There is a small percentage of the population that gets addicted [to tanning],” said Brenda Cartmel, study first author and senior research scientist at the Yale School of Public Health. “Ultimately, we hope that we might be able to develop new interventions that would help those  people.”

The study builds on past hypotheses that tanning addiction may have a biological underpinning, Cartmel said. Recent research has indicated that ultraviolet light can trigger the production of endorphins, a type of neurotransmitter.

One caveat of the study is that it uses a relatively small population, Cartmel said. The study will have to be replicated by other researchers before any further studies can be carried out on the PTCHD2 finding. Future research could help develop new tools for identifying people at a high risk for certain types of skin cancer, as well as improve existing treatments for tanning dependence.

“We’re hoping that this [study] is going to encourage other people to do research in this area,” Cartmel said.

The study was published in Experimental Dermatology on July 16.