DISSERTATION RESEARCH: Population Genetics of Caenorhabditis elegans

线虫秀丽线虫为我们提供了一个进化之谜。它很小，分布广泛，有能力快速增长人口。然而，与预期相反，基因变异非常低。这项研究解决了这一悖论背后的原因。两个关键过程可能导致多态缺失：种群结构和交配系统。通过利用微卫星和DNA序列数据，我们建议估计种群结构和基因流动。连锁不平衡的衰减将被用来估计自交率。将使用将在当地收集的种群以及可公开获得的菌株。从土壤中分离线虫的一个主要困难在于将其与其他形态相似的物种区分开来。我们开发了一种新的物种诊断技术，比传统方法更快速。这项技术将极大地增强线虫作为进化遗传学家的模式生物的吸引力。这项研究将有助于我们理解线虫的进化史，目前对线虫的进化史知之甚少。

The nematode Caenorhabditis elegans presents us with an evolutionary puzzle. It is small, widespread and capable of rapid population growth. Yet, contrary to expectations, genetic variation is very low. This research addresses the reasons behind this paradox. Two key processes might contribute to the lack of polymorphism: population structure and mating system. By employing microsatellite and DNA sequence data, we propose to estimate population structure and gene flow. Decay of linkage disequilibrium will be used to estimate selfing rates. Populations to be collected locally, as well as publicly available strains will be used. A major difficulty in isolating C. elegans from soil lies in distinguishing it from other morphologically similar species. We have developed a novel technique for species diagnosis, which is more rapid than conventional methods. This technique will vastly enhance the appeal of C. elegans as a model organism for evolutionary geneticists. The study will contribute a great deal to our understanding of the evolutionary history of C. elegans, about which very little is known presently.