Double-strand break repair is a crucial cellular process that fixes severe DNA damage, where both strands of the DNA helix are broken. This type of damage can occur due to various factors, including radiation, chemicals, or errors during DNA replication. Cells utilize specialized mechanisms to detect and repair these breaks, ensuring the integrity of the genetic material. There are two main pathways for repairing double-strand breaks: homologous recombination and non-homologous end joining. Homologous recombination uses a sister chromatid as a template for accurate repair, while non-homologous end joining directly joins the broken ends together, which can sometimes lead to errors. Both pathways are essential for maintaining genomic stability.