Kübra Aykan, İlknur Altuntaş, Oytun Erbaş

Demiroglu Science University, Experimental Medicine, Istanbul, Türkiye

Keywords: Base excision repair, cockayne syndrome, DNA repair, homologous recombination, nucleotide excision repair, xeroderma pigmentosum.


The deoxyribonucleic acid (DNA) of living organisms is damaged by exogenous and endogenous agents. These damages are repaired by a series of repair mechanisms. These repair mechanisms function both directly and indirectly. Photoreactivation, repair by O6-methylguanineDNA-methyltransferase, base-excision repair, nucleotide-excision repair, DNA double-strand break repair, homologous recombination repair, non-homologous end-joining, and mismatch repair are some examples of these mechanisms. Many damages, such as DNA strand breakage in the genome and base-base mismatches during replication, are repaired by various repair systems. There are some anomalies and disorders that develop when damage cannot be repaired or when the repair processes are impaired. These include xeroderma pigmentosum, Cockayne syndrome, Bloom syndrome, Werner syndrome, Huntington's disease, ataxia-telangiectasia, Nijmegen breakage syndrome, and Fanconi anemia. The functioning of DNA repair systems and the diseases caused by their defects are discussed in this review.

Cite this article as: Aykan K, Altuntaş İ, Erbaş O. DNA repair mechanisms: DNA repair defects and related diseases. D J Med Sci 2022;8(3):130-140.

Data Sharing Statement:
The data that support the findings of this study are available from the corresponding author upon reasonable request.

Author Contributions

Writing the article: K.A.; Control/supervision: ‹.A.; Critical review: O.E.

Conflict of Interest

The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Financial Disclosure

The authors received no financial support for the research and/or authorship of this article.


The figures used in this review were created with BioRender (BioRender.com).