The risk of skin cancer does not fall only on people with fair skin or those who tan slowly. It can be higher for individuals carrying a specific genetic mutation that shapes how the skin responds to sunburn and how quickly the body recovers from UV damage. Inna Kholandra of MyGenetics discussed these findings with socialbites.ca as part of a broader look at genetic risk factors.
Ultraviolet radiation is a unique component of sunlight that can penetrate deep into the skin. It damages DNA and leads to mutations that can accumulate over time. The body does have three key defenses against tumor formation: a pigment called melanin that protects skin tone, the repair system that fixes UV-induced DNA damage, and the immune-like process that targets and eliminates cells with severe DNA damage.
Researchers at MyGenetics analyzed a broad population sample and found that a majority of people in a Russian cohort produce enough melanin to tan well and often avoid sunburn, reducing their overall risk. About one third have fair skin and produce less melanin, which increases the likelihood of sunburn and, in turn, skin cancer risk. These individuals tend to adjust their behavior by using sunscreen and wearing protective clothing, which helps keep their risk nearer the population average. Yet those who naturally tolerate sun exposure may skip sunscreen, potentially raising melanoma risk when they do not protect themselves.
A notable factor is a specific mutation in the XRCC1 gene, which governs the rate at which UV-damaged DNA is repaired. DNA repair often introduces errors, so the body may benefit from eliminating mutant cells rather than fixing every damaged copy. The research indicates that moderate DNA repair speed after sunburn may provide a balance that reduces cancer risk by allowing the body to identify and remove problematic cells more reliably. In the studied population, about 46% showed moderate DNA repair capacity, associated with an average cancer risk level.
Remarkably, around 42% of Russians in the same study displayed a higher DNA repair rate in skin cells damaged by UV light. While this means the skin recovers quickly from sunburn, it also allows more damaged cells to survive, which can elevate melanoma risk and potentially increase tumor aggressiveness if cancer develops. In contrast, a smaller segment of roughly 12% showed a lower rate of DNA damage recovery after UV exposure, according to the researchers.
Experts emphasize the value of understanding personal DNA repair capacity when assessing sun-related cancer risk. Knowing one’s level of protection against ultraviolet radiation can inform decisions about sun exposure and protective measures. In particular, interpreting how sunburn risk translates to long-term cancer risk helps individuals tailor prevention strategies that fit their unique genetic profile.
Overall, these insights underscore the importance of testing for genetic factors that influence UV sensitivity and DNA repair. Such testing can illuminate how dangerous sunburn might be for an individual and guide practical steps to reduce risk, especially for those who may not exhibit obvious signs of vulnerability. This perspective aligns with a cautious approach to sun safety that prioritizes balanced sun exposure, protective clothing, and informed use of sunscreen based on personal genetic information and regional UV levels.