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What is a DNA damage caused? |
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Answer» Ultraviolet and other types of radiation can damage DNA in the form of DNA STRAND breaks. This involves a cut in one or both DNA strands; double strand breaks are especially DANGEROUS and can be mutagenic, since they can potentially affect the expression of multiple genes. UV-induced damage can also result in the production of pyrimidine dimers, where COVALENT cross-links occur in cytosine and thymine residues. The most common pyrimidine dimers are cyclobutane pyrimidine dimers (CPD) and pyrimidine (6-4) pyrimidone photoproducts (6-4PP). CPD and 6-4PP are the most frequent DNA mutations FOUND in the p53 protein in skin cancers. Pyrimidine dimers can disrupt polymerases and prevent proper REPLICATION of DNA. |
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