Scanning the genome for QTL affecting the recombination process in the male and female cattle germline

We herein study genetic recombination in three dairy cattle population from France, New-Zealand and The Netherlands. We apply a new phasing algorithm extracting familial information suited for large half-sib families to reconstruct haplotypes and detect cross-overs. The software is robust to genotyping errors and map errors (genome builts still contain errors for non-model organisms). We identify more than 2,000,000 cross-over events in sperm cells transmitted by 2942 sires to 94,049 offspring, and more than 500,000 cross-over events in oocytes transmitted by 10,943 cows to 23,850 offspring. The estimated number of cross-overs per gamete and its accuracy were influenced by the family structure (number of offsprings, parents and grand-parents genotyped). The average number of cross-overs in males (24.0) was larger than in females (21.8), even after correction for family structure. In males, recombination rates were higher closer to telomeres whereas in females, recombination rates dropped at both centromeres and telomeres (probably as a result of lower informativity). The heritability of the global recombination rate was close to 0.20 in males and to 0.10 in females and the genetic correlation was ~0.70, indicating that common genes are influencing both traits. Genome-wide association studies clearly confirmed QTL located close to REC8 and RNF212 in males. The QTL associated to REC8 was also detected in females and there was a positive correlation between QTL effects in males and females. The QTL associated to REC8 accounted for ~10% of the genetic variance in both males and females.