Researchers have for the first time have measured genomic DNA changes occurring in skin cells and established that ultraviolet (UV) light mutations are common. However, the National Institute of Environmental Health Sciences team led by Dmitry Gordenin found that the level of UV damage was much lower on Black people compared to white people.

Skin damage due to mutations lead to cancer

Usually, our skin DNA tends to suffer damage from outside the body and inside resulting in genomic DNA mutations that can result in cancer. Interestingly, UV light is the main mutation source by cellular metabolism by-products such as free radical and DNA copying errors during cell division can lead to these genomic changes. Despite the mutation-causing mechanisms being known, in the past, no one has accurately measured the contribution from each source.

Fascinatingly, the new study quantified the number of genomic changes each type causes through sequencing of skin cell genomes from 21 white and black individuals aged 25 to 79 years. Findings indicate that the amount of genomic changes due to metabolic by-products tends to accumulate as one gets old but the changes due to UV are unrelated to one’s age. Equally, researchers demonstrated that UV light genomic changes were common even in skin cells shielded from direct sunlight but were less prevalent on Black people.

High melanin levels protect black people from harmful sunlight UV

According to the researchers, Black people might be protected from UV light because of the higher melanin levels. To support the hypothesis is the fact that skin cancer is less prevalent in Black people compared to white individuals. In general, the new study accurately estimates genomic changes occurring in skin cells because of different DNA damage types. Equally the study provides the normal range of somatic genomic changes in different ages and races thus offering a foundation for future research.

The authors indicated that this study is important as it offers an accurate estimate of changes that occur on skin cells and provides insight correlation between race and skin cancer.