Factors such as UV radiation chemical and oxidative stress can cause DNA lesions

UV light damages DNA by inducing mutations effecting cell proto_oncogenesand tumor suppressors raising the risk of skin cancer

Recent studies have shown that short strands of toxic RNAS can contribute to DAN damage particularly in neurodegenerative disease like
Alzheimer's

Oxidative stress, caused by excess ROS, and DNA damage, triggered in response to different sources, are countered and resolved by specific mechanisms, allowing the normal physiological equilibrium of cells and tissues to be restored.
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Linking Oxidative Stress and DN

Most spontaneous changes in DNA are temporary but can lead to significant issues of not repaired

Scientific investigations have revealed that the majority of cancer causing chemicals or chemical carcinogens act through genotoxic or DNA damaging mechanisms which involves covalent binding of chemical to DNA