Why recombination hotspots?

Meiotic recombination is the process by which DNA is exchanged between parental chromosomes during the production of gametes in eukaryotes. This phenomenon has important implications for fertility, genetic diversity and genome stability. Intriguingly, not all regions of the genome are equally susceptible to recombine during meiosis. Instead, in many eukaryotes, recombination events are concentrated in short genomic segments called recombination hotspots. Since the first discovery of recombination hotspots, several theories have emerged to explain their existence. In this review, we discuss the relevance of these theories in regards of recent advances in characterizing the diversity and determinants of fine-scale recombination landscapes. Finally, we outline new research avenues for elucidating the evolutionary origins of recombination hotspots.