Dissertation Research: Geographic variation in Dmrt1 in the North American green frog

这项提案调查了决定胚胎是男性还是女性的过程。这些过程在物种之间可能差异很大，但其他特征在物种之间更为保守。研究人员先前的工作表明，北美绿色青蛙和人类共享决定胚胎是雄性还是雌性的重要基因组部分。重要的是，研究人员发现DMRT 1基因对人类雄性性腺发育为正常睾丸至关重要，在绿色青蛙的发育中也很重要。研究人员还注意到郊区绿色青蛙发育的普遍异常。这可能表明人类来源的污染物干扰了青蛙的发育。这项工作是在康涅狄格州的绿色青蛙身上进行的。然而，绿色青蛙分布在美国的一半和加拿大的部分地区，并且在该范围内发生变化。此外，对一种欧洲青蛙和一种日本青蛙的研究表明，在整个物种范围内，种群之间存在差异。该项目将研究基因DMRT 1和其他与美国各地绿色青蛙发育相关的基因组区域的基因组变异。这个项目将大大推进我们对发展的遗传基础在一个大的地理区域中是多么可变的理解。它还将开始显示全国各地的环境条件对青蛙发展的影响程度。这项工作将以各种方式向公众分发，包括在线博客和K-12教师的客座讲座。利用从该物种范围内代表性地区的雄性和雌性绿色青蛙中收集的组织样本，研究人员将测试DMRT 1等位基因频率和连锁的地理变异。此外，研究人员还将测试一组遗传标记是否与雄性和雌性特有的特定染色体相关联，这些遗传标记在整个物种范围内是否存在类似的联系。具有不同程度的这种联系的地理区域，无论是DMRT 1还是其他标记，都将指示物种范围的区域，其中环境条件更有可能影响驱动胚胎成为男性或女性的过程。

This proposal investigates the processes that determine if an embryo becomes a male or female. These processes can differ widely among species, but other features are more conserved between species. Previous work by the researchers showed that the North American green frog and humans share portions of the genome that are important for determining whether an embryo becomes a male or female. Importantly, the researchers discovered that the gene DMRT1, which is critical for human male gonads to develop as normal testes, is also important in green frog development. The researchers also noted widespread abnormalities in green frog development in suburban neighborhoods. This might indicate that human-derived contaminants interfere with how frogs develop. That work was conducted on green frogs in Connecticut. However, green frogs range across half of the United States and parts of Canada, and variation occurs across that range. In addition, work in one European and one Japanese frog species shows variation among populations across the species' range. This project will study the genomic variation in the gene DMRT1 and other genomics regions linked to development in green frogs across the United States. This project will substantially advance our understanding of how variable the genetic basis of development is across a large geographic area. It will also begin to show the extent to which environmental conditions across the country impact frog development. The work will be distributed to the public in a variety of ways including online blogs and guest lectures for K-12 teachers. Using tissue samples collected from male and female green frogs from representative regions across the species' range, the researchers will test for geographic variation in allele frequencies and linkage for DMRT1. Additionally, the researchers will test whether a set of genetic markers shown to be linked with particular chromosomes specific to males and females are similarly linked across the species range. Geographic areas with varying degrees of this linkage, either for DMRT1 or the other markers, will indicate regions of the species' range where environmental conditions are more likely to influence the processes driving whether an embryo becomes male or female.