在蝶中为哈尔丹规则的多基因解释
Tianzhu Xiong1, Shreeharsha Tarikere1, Neil Rosser1
1Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138.
概括
蝶中的混合不相容性并不能用主导理论来解释. 相反,性别染色体和自体之间不平衡的基因流动导致了这些问题,特别是在女性身上,这表明多基因杂交不兼容是常见的.
科学领域:
- 进化生物学是进化的生物学.
- 遗传学 是一个遗传学.
- 动物学 动物学
背景情况:
- 哈尔丹规则指出,异性杂交的杂交物不太适合.
- 大X/Z效应表明性别染色体是混合不相容的关键.
- 对性染色体的支配理论是这些规则的拟议机制.
研究的目的:
- 研究哈尔丹规则背后的机制以及蝶杂交中的大X/Z效应.
- 测试主导理论对 Papilio 和 Heliconius 蝶中的杂交不兼容性的适用性.
- 为观察到的混合不兼容性提出另一种解释.
主要方法:
- 在Papilio和Heliconius蝶中分析杂交不兼容性.
- 将遗传数据与主导理论预测进行比较.
- 研究Z染色体和自体体之间的多位点内进模式.
- 在定量特征位置 (QTL) 映射中控制统计链接.
主要成果:
- 主导理论无法解释观察到的混合不相容性.
- 杂交品种的缺陷与Z染色体和自体体之间的不平衡的多位置内侵关系.
- 一个多基因解释,涉及到Z-自体体内向不平衡,预测了哈尔丹规则和大X/Z效应.
- 统计链接可以创建虚假的大效果QTL,掩盖潜在的多基因遗传.
结论:
- 多基因杂交不兼容性,由Z-自体内侵入驱动,在蝶中可能很普遍.
- 拟议的多基因模型解释了混合不相容的既定规则.
- 进一步的研究应该考虑到统计链接在映射混合不兼容性时.
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