Scientists at the Washington State University School of Molecular Biology in the United States have discovered that exposure to ultraviolet light causes a previously unknown type of DNA damage that leads to aggressive skin cancer, reports the Cell Report edition, briefly about scientific work reported in press release at Phys.org.
The researchers irradiated the yeast cells of 150 colonies with ultraviolet light for eight seconds 15 times over a month. After that, DNA was isolated from the cells, which was subjected to full genome sequencing, that is, the complete nucleotide sequence in the double strand was established. They were able to identify 50 thousand mutations caused by ultraviolet light. Moreover, about half of the mutations were associated with the development of melanoma.
Until now, it was believed that UV damage is limited to two DNA bases: cytosine (C) or thymine (T). However, scientists have found that mutations also sometimes affect adenine (A). At the same time, even a single and short-term exposure to ultraviolet B (315-280 nanometers), which is part of sunlight, also causes atypical mutations.
Skin cancer is one of the most deadly types of malignant tumors, as it quickly leads to the formation of metastases. One of the risk factors is prolonged exposure to direct sunlight.