Recombination landscape of hexaploid bread wheat reveals genes controlling recombination and gene conversion frequency

Sequence exchange between homologous chromosomes through crossing over and gene conversion is highly conserved among eukaryotes, contributing to genome stability and genetic diversity. Lack of recombination limits breeding efforts in crops, therefore increasing recombination rates can reduce linkage-drag and generate new genetic combinations. We use computational analysis of open access data from 13 recombinant inbred mapping populations to assess crossover and gene conversion frequency in the hexaploid genome of wheat (Triticum aestivum). We find that high frequency crossover sites are shared between populations and that closely related parental founders lead to populations with more similar crossover patterns. We have identified QTL for altered gene conversion and crossover frequency and confirm functionality for a novel candidate RecQ helicase gene that belongs to an ancient clade that is missing in some plant lineages. Harnessing the RecQ helicase has the potential to break linkage-drag utilizing widespread gene conversions conserved across recombination sparse centromeric regions.