Scientists at the University of Rochester recently identified a protein that helps to repair DNA damage caused by reactive oxygen species (ROS). ROS are chemicals that can be formed by exposure to radiation but may also occur as a normal byproduct of cellular activities. Importantly, DNA damage caused by ROS can lead to permantent changes, mutations, and trigger the abnormal cell reproduction seen in cancer. The DNA protecting protein, known as SIRT6, is brought to the parts of DNA that have been cut in half by the ROS. Once there, they help to repair the damage. Because cancer results from mutation, it is important to understand how mutations are prevented.
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