Genetics of Haldane's Rule in Caenorhabditis

Haldane的规则是这样观察到的：“当两个不同动物种族的F1后代中有一个性别缺失、罕见或不育时，这个性别就是杂合性（heterozygous [heterogamametic] gender）”（Haldane, 1922）。在隐杆线虫属中，霍尔丹法则在C. briggsae::C.中被观察到。remanei混合动力车。这种组合的实现是通过单倍x杂交体向雌性的性转化。杂种性转化可能是由性别决定基因之间的异常相互作用造成的。这一假设将通过绘制抑制与C. briggsae和C. remanei性别决定基因相关的杂交性转化表型的自然变异来验证。在这些物种中，每一种都有一种这样的变异。性转化变异的定位将利用单核苷酸多态性（snp）作为遗传标记。该项目的目标是将杂交性转化变体映射到核苷酸上。这将分两个阶段完成。通过单虫PCR分析重组染色体，将获得0.1 μ（0.1%重组）的分辨率。根据所涉及的基因组区域，该分辨率将对应于5,000到150,000 bp之间。增加的分辨率（0.0001 mu）将通过基于人群的分析来实现，该分析旨在检测相邻snp之间的重组。这项工作将进一步加深对物种形成的进化遗传学的理解

Haldane's rule is the observation that "when in the F1 offspring of two different animals races one sex is absent, rare, or sterile, that sex is the heterozygous [heterogametic] sex" (Haldane, 1922). In the nematode genus Caenorhabditis, Haldane's Rule is observed in C. briggsae::C. remanei hybrids. Implementation in this combination is through sexual transformation of haplo-X hybrids into females. Hybrid sexual transformation likely results from dysgenic interactions among sex determination genes. This hypothesis will be tested by mapping naturally occurring variants that suppress the hybrid sexual transformation phenotype relative to the sex determination genes of C. briggsae and C. remanei. One such variant has been identified in each of these species. Mapping of sexual transformation variants will utilize single-nucleotide polymorphisms(SNPs) as genetic markers. The goal of this project is to map hybrid sexual transformation variants to the nucleotide. This will be accomplished in two stages. A resolution of 0.1 mu (0.1% recombination) will be achieved by analysis of recombinant chromosomes through a single-worm PCR assay. Depending on the genomic region involved, this resolution will correspond to between 5,000 to 150,000 bp. Increased resolution (0.0001 mu) will be achieved through a population-based assay designed to detect recombination between adjacent SNPs. This work will further the understanding of the evolutionary genetics of species formation.--