Distribution of meiotic recombination sites.

Meiotic recombination generates gene conversion and crossover events that are distributed heterogeneously in the genome. Studies in yeast show that initiation of recombination, which occurs by the formation of DNA double-strand breaks, determines the distribution of gene conversion and crossover events that take place in nearby intervals. Recent data in humans and mice also indicate the presence of highly localized initiation sites that promote crossovers clustered around the region of initiation and seem to share common features with sites in yeast. On a larger scale, chromosomal domains with various recombination rates have been identified from yeast to mammals. This indicates a higher level of regulation of recombination in the genome with potential consequences on genome structure.