The lowest NCO gene conversion rate
You to definitely domain stands out once the a beneficial recombinational wilderness. No CO otherwise gene conversion experiences is thought of within the a more or less eight hundred kb part surrounding the 2 linked sex devotion genetics, csd and fem (Extra document step 1: Profile S14). We suggest that, just like the heterozygosity away from csd determines the brand new intercourse of honeybee [56,57] and you will diploid homozygotes are sterile guys, gene sales contained in this domain name will be disadvantageous. As gene conversion process are relevant each other that have CO and you will NCO occurrences, all of the recombination would be abolished to quit homogenization. A lack of recombination plus forces the 2 loci to act while the just one haplotype.
The influence stands inside the hitting compare to an earlier declare that found excessively large CO pricing in the vicinity of new csd locus. A possible quality of the contradictory claims is the fact while in the newest instantaneous area of the family genes there’s no recombination, that is counterbalanced by unusually higher costs in the covers proximal toward desert. A reduced resolution studies manage discover the higher cost regarding the covers. In keeping with it we to see a leading peak away from recombination inside new instant vicinity of plateau (Extra document step 1: Figure S14).
All of our study increase the belief one public hymenoptera has one another higher and you can highly changeable crossing-more than cost. In reality, the interest rate varied between 0 and https://datingranking.net/joingy-review/ you will 197 cM/Mb whenever counted into the non-overlapping two hundred kb windows round the chromosomes (Profile step three, Shape S8 from inside the A lot more file 1 and you can Table S6 when you look at the More file dos), recommending this new very uneven delivery out of crossovers about genome. The newest figure away from 37 cM/Mb, when you are highest to possess pet, has been less than that viewed for some fungi and you will protozoans, where cost in excess of 60 cM/Mb are reported . Towards best of the studies, this new estimate indicates increased crossing-over rates than just present in people plant or animal.
While our study finds evidence consistent with several theoretical predictions, cause and effect are always hard to disentangle from correlation alone. For example, in principle the diversity/crossing-over coupling is also consistent with the notion that crossing over occurs preferentially in domains of high diversity and with the notion that crossing over is mutagenic . Similarly, the correlation between recombination rate and GC content is consistent with both the possibility that crossing over forces a high GC content and with the possibility that a high GC content favors increased crossing over. The conventional wisdom holds that recombination forces heteroduplexes within which mismatches require resolution. If this resolution is biased towards G and C residues (biased gene conversion), then a correlation between GC and recombination rate is expected . Previous analyses in honey bee have demonstrated fixation biases toward GC in high recombination parts of the genome . Evidence to support this direction for the causal arrow requires SNP analysis showing a bias to AT- > GC SNPs being fixed (or otherwise favored) compared to GC- > AT SNPs at sites of recombination. The key events here are most probably crossover-associated gene conversion events, but for these we cannot determine the direction of conversion and we are likely to be missing the majority of them. In our identified NCO events, if u is the number of AT > GC SNPs per A or T and v is the number of GC > AT SNPs per G or C, then the ratio of u/v is 1.06, which is slightly greater than the null (from stochastic simulations with 10,000 repeats: P <0.08). Being on the edge of significance, we cannot robustly say that NCO is or is not associated with GC-biased gene conversion.