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Updated: Apr 2, 2026
Using Next Generation Sequencing to Identify Mutations Associated with Repair of a CAS9-induced Double Strand Break Near the CD4 Promoter
Published on: March 31, 2022
Genomic approaches to DNA repair and mutagenesis
John J Wyrick1, Steven A Roberts2
1School of Molecular Biosciences, Washington State University, Pullman, WA 99164, USA; Center for Reproductive Biology, Washington State University, Pullman, WA 99164, USA.
Abstract:
DNA damage is a constant threat to cells, causing cytotoxicity as well as inducing genetic alterations. The steady-state abundance of DNA lesions in a cell is minimized by a variety of DNA repair mechanisms, including DNA strand break repair, mismatch repair, nucleotide excision repair, base excision repair, and ribonucleotide excision repair. The efficiencies and mechanisms by which these pathways remove damage from chromosomes have been primarily characterized by investigating the processing of lesions at defined genomic loci, among bulk genomic DNA, on episomal DNA constructs, or using in vitro substrates. However, the structure of a chromosome is heterogeneous, consisting of heavily protein-bound heterochromatic regions, open regulatory regions, actively transcribed genes, and even areas of transient single stranded DNA. Consequently, DNA repair pathways function in a much more diverse set of chromosomal contexts than can be readily assessed using previous methods. Recent efforts to develop whole genome maps of DNA damage, repair processes, and even mutations promise to greatly expand our understanding of DNA repair and mutagenesis. Here we review the current efforts to utilize whole genome maps of DNA damage and mutation to understand how different chromosomal contexts affect DNA excision repair pathways.
Insights
DNA repair pathways maintain genomic stability by removing DNA lesions. Whole genome mapping reveals how chromosomal context influences DNA excision repair efficiency and mutagenesis.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- DNA damage poses a constant threat to cellular integrity and genomic stability.
- Cells employ multiple DNA repair mechanisms, including base excision repair (BER) and nucleotide excision repair (NER), to counteract DNA lesions.
- Traditional methods for studying DNA repair often overlook the influence of diverse chromosomal contexts.
Purpose of the Study:
- To review current efforts in mapping DNA damage and repair across the whole genome.
- To understand how varying chromosomal contexts (heterochromatin, euchromatin, transcribed regions) impact DNA excision repair pathways.
- To explore the implications of context-dependent repair for mutagenesis.
Main Methods:
- Utilizing whole genome mapping techniques to identify DNA damage and mutation patterns.
- Analyzing repair pathway activity in different genomic regions.
- Comparing repair efficiencies across diverse chromosomal structures.
Main Results:
- DNA repair pathway efficiencies are significantly influenced by the local chromosomal environment.
- Heterochromatic regions and actively transcribed genes present distinct challenges and efficiencies for DNA repair.
- Context-specific repair mechanisms contribute to the overall mutation landscape.
Conclusions:
- Whole genome mapping provides critical insights into the context-dependent nature of DNA repair.
- Understanding how chromosomal structure affects DNA repair is essential for comprehending mutagenesis.
- Future research should focus on integrating genomic context into DNA repair and mutagenesis studies.
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