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一个因素的性别决定在没有女性化和男性化突变之间的联系的情况下演变
Michael F Scott1, Simone Immler1
1School of Biological Sciences, University of East Anglia, Norwich Research Park , Norwich NR4 7TJ, UK.
Proceedings. Biological sciences
|July 9, 2024
概括
分离的性别通过一因子的性别决定进化,当双重突变物发展成男性或女性时. 这揭示了性别确定系统的替代进化途径,与经典的两因素模型不同.
科学领域:
- 进化生物学是进化的生物学.
- 遗传学 遗传学 是一个
- 发育生物学是发展生物学.
背景情况:
- 不同性别的进化需要突变来促进女性和男性的发展.
- 经典模型提出了双因素的性别决定,男性和女性在两个遗传位置上有所不同,假设双重突变是无菌的.
- 然而,一些物种表现出单因子的性别决定,性发育由单个位置控制.
研究的目的:
- 为了研究导致一个因素的性别决定的进化途径.
- 确定哪些条件下,一个因素的性别决定从共性向演变.
- 探索双重突变者的生存能力如何影响性别确定系统的进化.
主要方法:
- 对等位基固定和性别决定进化的理论建模.进化.
- 对女性化和男性化等位基因传播的遗传条件的分析.
- 一个因素和两个因素的性别确定模型的比较.
主要成果:
- 一个因素的性别决定在双重突变是可行的并且发展为男性或女性时演变.
- 如果双重突变是男性,女性化等位基因会固定;如果双重突变是女性,男性化等位基因会固定.
- 另一个位点建立了基于等位基优势的XY或ZW系统,女性化和男性化在与经典模型相似的条件下传播,但不需要链接.
结论:
- 双重突变的生存能力为性别决定进化提供了替代途径.
- 一个因素的性别决定可以在没有涉及的等位基因之间的联系的情况下出现.
- 区分这些进化途径需要经验数据关于性别决定的遗传学.
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