DNA polymerase beta also known as DNA pol β, POLB is a DNA polymerase involved in base excision and repair, also called gap-filling DNA synthesis. DNA polymerase beta plays a crucial role in DNA repair and replication, particularly in synthesizing short DNA fragments during single-strand break repair. DNA polymerase beta′s ability to accurately incorporate nucleotides maintains genomic integrity, as errors can lead to mutations and genomic instability, which are hallmarks of various diseases, including cancer. DNA polymerase beta also interacts with several proteins involved in DNA damage response, such as proliferating cell nuclear antigen (PCNA), which enhances processivity during DNA synthesis.