Changes in the Level of DNA Methylation in under the Influence of Physical and Chemical Factors.

The effects of physical factors such as radiation (electromagnetic, microwave, infrared, laser, UVC, and X-ray) and high temperature, as well as chemical factors (controlled atmosphere) on the level of global DNA cytosine methylation in ATCC 10231 cells were investigated. Prolonged exposure to each type of radiation significantly increased the DNA methylation level. In addition, the global methylation level in cells increased with the incubation temperature. An increase in the percentage of methylated DNA was also noted in cells cultured in an atmosphere with reduced O. In contrast, in an atmosphere containing more than 3% CO and in anaerobic conditions, the DNA methylation level decreased relative to the control. This study showed that prolonged exposure to various types of radiation and high temperature as well as reduced O in the atmosphere caused a significant increase in the global DNA methylation level. This is most likely a response protecting DNA against damage, which at the same time can lead to epigenetic disorders, and in consequence can adversely affect the functioning of the organism.