Abstract
With the elucidation of the structure of DNA in 1953, it became possible to think in molecular terms
about how recombination occurs and how it relates to the repair of DNA damage. Early molecular models,
most notably the seminal model of Holliday in 1964, have been followed by a succession of other proposals
to account for increasingly more detailed molecular biological information about the intermediates of recombination
and for the results of more sophisticated genetic tests. Our current picture, far from definitive, includes
several distinct mechanisms of DNA repair and recombination in both somatic and meiotic cells, based on
the idea that most recombination is initiated by double-strand breaks.