Double-strand breaks (DSBs) in chromosomal DNA can induce both homologous
recombination (HR) and non-homologous end-joining (NHEJ). Recently we showed that
single-strand nicks induce HR with a significant reduction in toxicity and mutagenic effects
associated with NHEJ. To further investigate the differences and similarities of DSB-and nick-
induced repair, we used an integrated reporter system in human cells to measure HR and
NHEJ produced by the homing endonuclease I-AniI and a designed 'nickase'variant that …