U.S.-Russia-Mongolia Joint Collaborative Research: Comparative Framework for North Asian Genetic Diversity

这项研究将使用人类基因组变异模式作为一种工具来检验关于北亚和美洲早期人类居住的假设，并评估特定性别的人口统计过程和自然选择在塑造北亚遗传多样性方面的相对影响。在遗传学中，对父系、母系或双亲遗传的谱系的研究可以为智人的起源和全球传播提供不同的见解。基因分析将应用于一个由16名男性组成的小组，每个小组来自6个西伯利亚种群。比较人类种群内部和种群之间的种内变异模式，以及这些基因座上人类和类人猿之间的差异水平，将能够测试自然选择的影响以及雄性和雌性有效种群数量的潜在差异。在这个西伯利亚确定小组中发现的信息性多态将在更大的北亚样本中进行基因分型，以便进一步测试语言、地理和遗传变异之间的关联，以及遗传漂移、迁徙和混合对北亚人口的影响。这些结果将有助于构建美洲早期人类不同阶段的更现实的殖民模式。这项研究的结果将增强我们对人类进化史的理解。重建亚洲人类进化的模式和过程是令人感兴趣的，因为从考古和古生物记录中没有很好地了解解剖学上的现代人离开非洲的最早传播路线。此外，该地区也是随后迁徙到日本、西伯利亚和美洲的源头。西伯利亚的31个土著民族，其中14个可用于该项目，为研究可能作用于早期现代人的进化力量提供了重要机会。直到最近，许多西伯利亚土著群体仍保留着传统的自给自足的经济和生活方式，这可能反映了新石器时代以前的人口结构。北亚种群，特别是那些适应最北端人类居住地区的寒带气候的种群，在基因上是细分的，基因漂移在西伯利亚形成变异模式方面发挥了关键作用。此外，西伯利亚人口的人口历史导致了语言和遗传变异之间不同寻常的密切联系。这项拟议的研究是首次尝试利用从同一组样本获得的数据来开发一个比较遗传框架。拟议的研究将直接解决人类学遗传学家目前面临的三大挑战。这里采用的多点方法将有助于理解：(1)人类基因组的哪些部分是可变的；(2)基因组和进化过程如何相互作用，产生观察到的多样性模式；(3)在不同的时间段和不同的种群中，每种力量的相对作用是什么。除了具有引人入胜的进化史外，西伯利亚原住民群体还代表着解决这些及时问题的理想模式系统。

Hammer0216732This research will use human genomic variation patterns as a tool for testing hypotheses concerning the early peopling of North Asia and the Americas and for assessing the relative effects of sex-specific demographic processes and natural selection in shaping North Asian genetic diversity. Within genetics, the study of lineages that are inherited paternally, maternally or biparentally can offer different insights into the origins and global dispersals of Homo sapiens. The genetic analyses will be applied to a panel of 16 males from each of 6 Siberian populations. Comparisons of intra-specific patterns of variation within and among human populations, and with levels of divergence between humans and great apes at these loci, will enable tests of the effects of natural selection and potential differences in male and female effective population sizes. Informative polymorphisms discovered in this Siberian ascertainment panel will be genotyped in a larger set of North Asian samples to allow further tests of the associations between linguistic, geographic, and genetic variation and the effects of genetic drift, migration, and admixture on North Asian populations. These results will be used to aid in constructing more realistic colonization models involving different stages for the early peopling of the Americas.Results from this research will enhance our understanding of the evolutionary history of our species. Reconstructing the patterns and processes of human evolution in Asia is of interest because the the earliest dispersal routes of anatomically modern humans out of Africa are not well understood from the archaeological and paleontological records. Further, this region is the origin for subsequent migrations to Japan, Siberia, and the Americas. The 31 native ethnic groups of Siberia, 14 of which are available for this project, offer significant opportunities to examine the evolutionary forces that may have acted on early modern human populations. Until very recently many native Siberian groups retained traditional subsistence economies and lifeways that may have reflected a pre-Neolithic population structure. North Asian populations, especially those adapted to boreal climates in the northernmost regions inhabited by humans, are genetically subdivided, and genetic drift has played a key role in shaping patterns of variation in Siberia. Furthermore, the demographic history of Siberian populations has led to an unusually strong association between language and genetic variation. The proposed research is a first attempt to develop a comparative genetic framework using data obtained from the same set of samples.The proposed research will directly address three major challenges that now face anthropological geneticists. The multiple locus approach to be taken here will help to understand: (1) which portions of the human genome are variable; (2) how genomic and evolutionary processes have interacted to generate observed patterns of diversity; and (3) what the relative roles of each of these forces have been over different periods of time and in different populations. In addition to having a fascinating evolutionary history, Native Siberian populations represent an ideal model system within which to address these timely issues.