What are mutations and what problems can they cause in DNA replication?
A mutation is a change that occurs in our DNA sequence, either due to mistakes when the DNA is copied or as the result of environmental factors such as UV light and cigarette smoke. Mutations can occur during DNA replication if errors are made and not corrected in time.
Which enzyme has a proofreading function for replication errors?
DNA polymerases
What might result from a replication error?
When Replication Errors Become Mutations. Incorrectly paired nucleotides that still remain following mismatch repair become permanent mutations after the next cell division. This is because once such mistakes are established, the cell no longer recognizes them as errors.
How often is a mistake made in DNA replication?
Errors during DNA Replication result in Mutations Mistakes occur about once in every 10,000 base pairs and can potentially be disastrous for an organism. There are various repair mechanisms that can fix these errors and, in the end, the observed error rate is very low (often less than one mistake/10 million bases).
How are double stranded breaks in DNA repair?
Double-strand DNA breaks are common events in eukaryotic cells, and there are two major pathways for repairing them: homologous recombination and nonhomologous DNA end joining (NHEJ). The diverse causes of DSBs result in a diverse chemistry of DNA ends that must be repaired.