repair synthesis

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repair synthesis The enzymatic excision and replacement of regions of damaged DNA. The defective single-stranded segments of DNA are cut out, correct bases are inserted using the complementary strand as a template, and these are interlocked by a DNA polymerase. A polynucleotide ligase joins the 2 ends of the broken strand to complete the repair. An example is the removal by a nuclease enzyme of a thymine dimer that has been induced by UV radiation of the DNA molecule.

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