DNA double strand breaks (DSB) are cytotoxic lesions that can lead to genome rearrangements and genomic instability, which are hallmarks of cancer. The two main DSB repair pathways are non-homologous end joining and homologous recombination (HR). While HR is generally highly accurate, it has the potential for rearrangements that occur directly or through intermediates generated during the repair process. Whole genome sequencing of cancers has revealed numerous types of structural rearrangement signatures that are often indicative of repair mediated by sequence homology. However, it can be challenging to delineate repair mechanisms from sequence analysis of rearrangement end products from cancer genomes, or even model systems, because the same rearrangements can be generated by different pathways. Here, we review homology-directed repair pathways and their consequences. Exploring those pathways can lead to a greater understanding of rearrangements that occur in cancer cells.

DNA 双链断裂 (DSB) 是细胞毒性损伤，可导致基因组重排和基因组不稳定，这是癌症的标志。两个主要的 DSB 修复途径是非同源末端连接和同源重组 (HR)。虽然 HR 通常非常准确，但它有可能直接或通过修复过程中产生的中间体发生重排。癌症的全基因组测序揭示了许多类型的结构重排特征，这些特征通常表明由序列同源性介导的修复。然而，从癌症基因组或什至模型系统的重排终产物的序列分析中描述修复机制可能具有挑战性，因为相同的重排可以通过不同的途径产生。这里，我们回顾了同源定向修复途径及其后果。探索这些途径可以更好地了解癌细胞中发生的重排。