Wang Long, Zhang Yanchun, Qin Chao, Tian Dacheng, Yang Sihai, Hurst Laurence D
State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, People's Republic of China.
State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, People's Republic of China
Proc Biol Sci. 2016 Oct 26;283(1841). doi: 10.1098/rspb.2016.1785.
Mutation rates and recombination rates vary between species and between regions within a genome. What are the determinants of these forms of variation? Prior evidence has suggested that the recombination might be mutagenic with an excess of new mutations in the vicinity of recombination break points. As it is conjectured that domesticated taxa have higher recombination rates than wild ones, we expect domesticated taxa to have raised mutation rates. Here, we use parent-offspring sequencing in domesticated and wild peach to ask (i) whether recombination is mutagenic, and (ii) whether domesticated peach has a higher recombination rate than wild peach. We find no evidence that domesticated peach has an increased recombination rate, nor an increased mutation rate near recombination events. If recombination is mutagenic in this taxa, the effect is too weak to be detected by our analysis. While an absence of recombination-associated mutation might explain an absence of a recombination-heterozygozity correlation in peach, we caution against such an interpretation.
突变率和重组率在不同物种之间以及基因组内的不同区域之间存在差异。这些变异形式的决定因素是什么?先前的证据表明,重组可能具有致突变性,在重组断点附近会出现过多的新突变。由于据推测驯化类群的重组率高于野生类群,我们预计驯化类群的突变率会升高。在这里,我们利用驯化桃和野生桃的亲子测序来探讨:(i)重组是否具有致突变性,以及(ii)驯化桃的重组率是否高于野生桃。我们没有发现证据表明驯化桃的重组率增加,也没有发现重组事件附近的突变率增加。如果在这个类群中重组具有致突变性,那么这种效应太弱以至于无法被我们的分析检测到。虽然缺乏与重组相关的突变可能解释了桃中不存在重组 - 杂合性相关性的现象,但我们对此类解释持谨慎态度。