在平分类社会昆虫中有害遗传变异的性别差异
Sara E Miller1,2, Michael J Sheehan1
1Laboratory for Animal Social Evolution and Recognition, Department of Neurobiology and Behavior, Cornell University, Ithaca, New York, USA.
Molecular ecology
|June 23, 2023
概括
像纸这样的哈普洛狄位物种,由于直接选择,在雄性中更有效地清除有害突变. 这项研究显示,雄性黄蜂的有害基因变异较少,这表明野生种群中存在大量有害突变.
科学领域:
- 进化遗传学的进化遗传学
- 人口基因组学是人口的基因组学.
- 分子进化的分子进化.
背景情况:
- 有害的基因变异降低了健康状况并导致疾病,但很难区分出低频率中性变异.
- 了解野生种群中有害变异的负担对于进化见解至关重要.
- 单双双体的生物,有单双体和双双体的性别,可能提供一个独特的系统来研究突变的清除.
研究的目的:
- 为了正式测试这种假设,有害的等位基因更有效地清除在 haploid 类型的 haplodiploid 类型的男性性别.
- 调查野生单双体群中雄性和雌性之间遗传变异的差异.
- 用性别之间的比较基因组学推断有害变异的存在和频率.
主要方法:
- 北方纸 (Polistes fuscatus) 的雄性和雌性之间的遗传变异 (错误和无意义) 的比较分析.
- 人口基因组学数据被用来评估等位基因频率和推断选择压力.
- 在两性中量化突变负载.
主要成果:
- 与雌性相比,雄性纸每一代表现出明显较少的误解和无意义变体.
- 变体频率的差异在罕见的误解和无意义变体中尤为明显.
- 男性的突变负载比女性低,这表明对有害等位基因的选择更有效.
结论:
- 这项研究提供了第一个正式的证据支持假设更高效的清除有害突变在平性雄性.
- 单双体昆虫的野生种群含有大量有害变种.
- 在平分类雄性中对有害基因的更强的选择对其他平分类物种的适应性和进化潜力产生影响.
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