A detailed understanding of how homologous recombination proceeds at the molecular
level in vivo requires the ability to detect in real time the appearance of specific
intermediates of DNA repair. The most detailed analysis of double-strand break (DSB) repair
in eukaryotes has come from the study of budding yeast, using an inducible site-specific HO
endonuclease to initiate recombination synchronously in nearly all cells of the population.
Polymerase chain reaction (PCR) and chromatin immunoprecipitation (ChIP) methods have …