Mismatch Repair

A mutational event that disrupts the superhelical structure of DNA has the potential to compromise the genetic stability of the entire cell. The DNA mismatch repair is a system whereby one can recognize and repair the erroneous insertion in the DNA sequence, correct the inappropriate deletion or the other problems that can arise during DNA replication and recombination.

It can also help repair some types of DNA damage. The whole system is extremely complex which highlights the importance of evolution on DNA fidelity.

There are two major ways of mismatch repairs: the long patch and the short patch. Long patch has the ability to repair all types of mismatches, although this [Page 1129]is usually by replication, and it can also excise tracts, which are up to several kilobases long. By contrast, short patch covers only a specific mismatch, which can remove about 10 nucleotides repairing specific damage to the genome.

However, the problems that can occur come from the fact that the mismatch repair is strand specific and that the newly synthesized strand may also include errors continued from parental strands, with researchers believing that further work might be able to make repairs easier and more effective.