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个体介质交叉率和大西洋鱼分布的遗传结构
Cathrine Brekke1,2, Susan E Johnston3, Tim M Knutsen4
1Institute of Ecology and Evolution, School of Biology, University of Edinburgh, Edinburgh, EH9 3FL, UK. cathrine.brekke@nmbu.no.
Scientific reports
|November 22, 2023
概括
雄性和雌性大西洋三文鱼之间的 meiotic 重组率和模式显著不同. 这些差异是遗传的和遗传上不同的,为重组进化提供了洞察力.
科学领域:
- 进化遗传学的进化遗传学
- 基因组学就是基因组学.
- 生殖生物学 生殖生物学
背景情况:
- 通过染色体交叉的介质性重组对于适当的染色体分离和遗传多样性至关重要.
- 重组率在物种,性别和个体之间有所不同,在大西洋鱼中已知性别特异性差异 (例如,雄性中的端粒交叉,雌性中的中心).
- 在个体层面上对这些性别特异性重组模式的遗传控制在很大程度上仍未被探索.
研究的目的:
- 调查大西洋鱼个体重组措施中的遗传变异.
- 为了确定重组数和性别之间的混杂的遗传性和遗传相关性.
- 了解鱼类中性别特异性重组模式背后的遗传结构.
主要方法:
- 对挪威大西洋三文鱼5000多个大型全兄弟姐妹家族的高密度SNP基因型的分析.
- 构建自体链接地图以量化重组计数 (CC) 和染色体内遗传混杂.
- 对重组特征的遗传性 (h2) 和性别间基因相关性的估计.
主要成果:
- 女性的交叉计数比男性高1.6倍,自体相链接地图较大 (2174 cM与1483 cM).
- 尽管交叉计数较低,但女性重组产生了8倍多的染色体内基因混杂,这是由于较少的端粒偏差.
- 重组数和混合在两性中都是可遗传的,但性别间的遗传相关性接近于零,表明有明显的遗传控制.
结论:
- 重组率和分布是雄性和雌性大西洋鱼的遗传特征.
- 这表明,在每个性别中都有可能存在独立的进化回组合轨迹.
- 这些发现为重组的遗传结构及其在真核生物中的进化提供了新的见解.
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