Meiotic recombination between repeated transposable elements in Saccharomyces cerevisiae.

We have measured the frequency of meiotic recombination between marked Ty elements in the Saccharomyces cerevisiae genome. These recombination events were usually nonreciprocal (gene conversions) and sometimes involved nonhomologous chromosomes. The frequency of ectopic gene conversion among Ty elements appeared lower than expected on the basis of previous studies of recombination between artificially constructed repeats. The conversion events involved either a subset of the total Ty elements in the genome or the conversion tract was restricted to a small region of the Ty element. In addition, the observed conversion events were very infrequently associated with reciprocal exchange.