Figure 1.
DNA damage and repair pathways. Different factors are responsible for initiating DNA damage such as radiation and reactive oxygen species which cause several types of lesions in the DNA double helix. The repair pathway involved in the process is dependent on the damaging agent and lesion generated. Base excision repair (BER), nucleotide excision repair (NER), non-homologous end joining (NHEJ), reactive oxygen species (ROS) and DNA mismatch repair (MMR).