DNA double-strand breaks can be repaired through ligation-based pathways (non-homologous end-joining) or replication-based pathways (homologous recombination) in eukaryotic cells. The decisions that govern these outcomes are widely viewed as a competition between factors that recognize DNA ends and physically promote association of factors specific to each pathway, commonly known as ‘pathway choice’. Here I review recent results in the literature and propose that this decision is better described as a sequential set of binding and end processing events, with non-homologous end joining as the first decision point. Physical association and co-localization of end resection factors with non-homologous end-joining factors suggests that ends are transferred between these complexes, thus the ultimate outcome is not the result of a competition but is more akin to a relay race that is determined by the efficiency of the initial end-joining event and the availability of activated DNA end-processing enzymes.

DNA 双链断裂可以通过真核细胞中基于连接的途径（非同源末端连接）或基于复制的途径（同源重组）进行修复。控制这些结果的决定被广泛视为识别 DNA 末端的因素之间的竞争，并在物理上促进特定于每个途径的因素的关联，通常称为“途径选择”。在这里，我回顾了文献中的最新结果，并建议将该决定更好地描述为一组顺序的结合和末端处理事件，非同源末端连接作为第一个决策点。末端切除因子与非同源末端连接因子的物理关联和共定位表明末端在这些复合物之间转移，