POLM

DNA polymerase mu (Pol μ), encoded by the POLM gene, belongs to the X-family of DNA polymerases. Common aliases include POLM_HUMAN and isoform 1 of DNA polymerase mu. It mediates non-homologous end-joining (NHEJ), a key pathway for double-strand DNA break repair, by catalyzing template-independent or microhomology-guided DNA synthesis during DSB ligation.
Dysregulated POLM activity disrupts NHEJ, leading to genomic instability and increased risk of cancers like breast and ovarian malignancies. Preclinical research is exploring small-molecule inhibitors of Pol μ to enhance the efficacy of DNA-damaging cancer therapies, as inhibiting its function can sensitize cancer cells to chemotherapy or radiation-induced DNA breaks.