Beck Jeffrey J, Hottenga Jouke-Jan, Mbarek Hamdi, Finnicum Casey T, Ehli Erik A, Hur Yoon-Mi, Martin Nicholas G, de Geus Eco J C, Boomsma Dorret I, Davies Gareth E
Avera Institute for Human Genetics, Avera McKennan Hospital & University Health Center, Sioux Falls, SD, USA.
Department of Biological Psychology, Behavioral and Movement Sciences, Vrije Universiteit, Amsterdam, the Netherlands.
Twin Res Hum Genet. 2019 Aug;22(4):210-219. doi: 10.1017/thg.2019.41. Epub 2019 Aug 5.
Twin registries often take part in large collaborative projects and are major contributors to genome-wide association (GWA) meta-analysis studies. In this article, we describe genotyping of twin-family populations from Australia, the Midwestern USA (Avera Twin Register), the Netherlands (Netherlands Twin Register), as well as a sample of mothers of twins from Nigeria to assess the extent, if any, of genetic differences between them. Genotyping in all cohorts was done using a custom-designed Illumina Global Screening Array (GSA), optimized to improve imputation quality for population-specific GWA studies. We investigated the degree of genetic similarity between the populations using several measures of population variation with genotype data generated from the GSA. Visualization of principal component analysis (PCA) revealed that the Australian, Dutch and Midwestern American populations exhibit negligible interpopulation stratification when compared to each other, to a reference European population and to globally distant populations. Estimations of fixation indices (FST values) between the Australian, Midwestern American and Netherlands populations suggest minimal genetic differentiation compared to the estimates between each population and a genetically distinct cohort (i.e., samples from Nigeria genotyped on GSA). Thus, results from this study demonstrate that genotype data from the Australian, Dutch and Midwestern American twin-family populations can be reasonably combined for joint-genetic analysis.
双胞胎登记处经常参与大型合作项目，并且是全基因组关联（GWA）荟萃分析研究的主要贡献者。在本文中，我们描述了来自澳大利亚、美国中西部（阿韦拉双胞胎登记处）、荷兰（荷兰双胞胎登记处）的双胞胎家庭群体，以及来自尼日利亚的双胞胎母亲样本的基因分型，以评估它们之间是否存在基因差异以及差异程度。所有队列的基因分型均使用定制设计的Illumina全球筛选阵列（GSA）进行，该阵列经过优化以提高针对特定人群的GWA研究的归因质量。我们使用从GSA生成的基因型数据的几种群体变异测量方法，研究了这些群体之间的基因相似程度。主成分分析（PCA）的可视化显示，与彼此、一个参考欧洲群体以及全球遥远群体相比，澳大利亚、荷兰和美国中西部群体之间的群体分层可以忽略不计。澳大利亚、美国中西部和荷兰群体之间的固定指数（FST值）估计表明，与每个群体和一个基因上不同的队列（即GSA基因分型的尼日利亚样本）之间的估计相比，遗传分化最小。因此，本研究结果表明，来自澳大利亚、荷兰和美国中西部双胞胎家庭群体的基因型数据可以合理地合并用于联合基因分析。
