During the transition from sexual to asexual reproduction, a suite of reproduction‐related sexual traits become superfluous, and may be selected against if costly. Female functional virginity refers to asexual females resisting to mate or not fertilizing eggs after mating. These traits appear to be among the first that evolve during transitions from sexual to asexual reproduction. The genetic basis of female functional virginity remains elusive. Previously, we reported that female functional virginity segregates as expected for a single recessive locus in the asexual parasitoid wasp Asobara japonica. Here, we investigate the genetic basis of this trait by quantitative trait loci (QTL) mapping and candidate gene analyses. Consistent with the segregation of phenotypes, we found a single QTL of large effect, spanning over 4.23 Mb and comprising at least 131 protein‐coding genes, of which 15 featured sex‐biased expression in the related sexual species Asobara tabida. Two of the 15 sex‐biased genes were previously identified to differ between related sexual and asexual population/species: CD151 antigen and nuclear pore complex protein Nup50. A third gene, hormone receptor 4, is involved in steroid hormone mediated mating behaviour. Overall, our results are consistent with a single locus, or a cluster of closely linked loci, underlying rapid evolution of female functional virginity in the transition to asexuality. Once this variant, causing rejection to mate, has swept through a population, the flanking region does not get smaller owing to lack of recombination in asexuals.

中文翻译：

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在无性寄生性黄蜂中，单个影响较大的QTL与女性功能初次使用有关

在从有性生殖向无性生殖过渡的过程中，一整套与生殖有关的性特征变得多余，如果代价高昂，可以选择这些生殖器。女性的处女功能是指无性的雌性在交配后不交配或不让卵受精。这些特征似乎是在从有性生殖到无性生殖转变过程中演变而来的第一个特征。女性功能童贞的遗传基础仍然难以捉摸。先前，我们报道了女性功能纯正性与无性寄生性黄蜂Asobara japonica中单个隐性基因座的预期分离。在这里，我们通过定量性状基因座（QTL）定位和候选基因分析来研究该性状的遗传基础。与表型的分离相一致，我们发现了一个单个QTL，其影响较大，跨越4.23 Mb，包含至少131个蛋白质编码基因，其中15个在相关性物种Asobara tabida中表现出性别偏向性表达。先前已鉴定出15个性别偏向基因中的两个在相关的有性和无性种群/物种之间存在差异：CD151抗原和核孔复合蛋白Nup50。第三个基因，激素受体4参与类固醇激素介导的交配行为。总体而言，我们的结果与单个位点或紧密联系的基因座簇相一致，这是女性向无性生活过渡时女性处女的快速进化的基础。一旦这种导致排斥交配的变种席卷了整个种群，由于无性繁殖者缺乏重组，侧翼区域就不会变小。