what you described as mismatch repair is better known as proofreading, which occurs during the S phase. "mismatch repair" occurs during the G2 phase, and corrects errors that proofreading might have missed
This good intro to explore molecular basic of dna damage & repair , which accumulation of imbalance turn to cellular senescence and then aging or cancer ( for cancer cell it will be keep balance by immune system , so if dna damage in our body involved immune system or immuno-senescence we will get cancer disease ... pollution , chronic inflammation and SARS-CoV infection will made people (biological) aged faster ) this may lead to explanation why organic living is important ! just reduce production and using industrialized goods like plastic while promote more recycle to create green environment. may help our body repair natural dna damage and delay biological aging ( we can not live forever but we may living healthy life till the last day ) * or we may found gene therapy that better repair dna damage in future ?
What is the difference between nucleotide excision repair and base excision repair? Is it that base excision involves the bases only and has DNA glycosylase whereas nucleotide excision repair uses endonucleases?
This is a late comment but I think nucleotide is for bulkier elements that were incorporated whereas base is for smaller stuff such as deamination or the misincorporation of uracil for thymine
