Dissertation Ressearch: Linkage Disequilibrium in Four Ethnically Diverse Human Populations: Selection and Demographic Effects

[73054]汤姆逊&；mah . d]两个基因的不同等位基因之间的非随机关联的全基因组模式，称为连锁不平衡（LD），目前还没有得到很好的理解。最近对高加索人群的研究揭示了LD的异质分布，这种模式与某些地区基因的自然选择作用相一致。本研究将确定LD在不同种族人群中的分布是否相似，并将通过在三种不同人群中表征LD的九个基因组区域来评估人口统计学对LD分布的影响。为了测量LD，将利用人类基因组计划提供的数据，确定103个遗传标记的等位基因关联。这项研究是在几个人群LD的比较表征，将有助于理解基因组进化。人类基因组中在几个不同种族的人群中显示出高水平LD的区域很可能包含在人类物种中经历选择的基因。发现经历过选择的基因与疾病研究有关，有助于理解人类生物历史。了解LD如何依赖于人口统计学，将有助于决定哪些人群适合用于复杂疾病和性状基因的LD定位。

0073054Thomson & MatherThe genome wide pattern of nonrandom association between different alleles of two genes, called linkage disequilibrium (LD), is not well understood. Recent work in a Caucasian population revealed a heterogeneous distribution of LD, a pattern consistent with the action of natural selection on genes in some regions. This study will determine whether LD is distributed similarly in ethnically diverse human populations and will evaluate the effects of demography on the distribution of LD by characterizing LD nine genomic regions in three diverse human populations. To measure LD, allelic associations will be determined for 103 genetic markers, chosen using the data available from the Human Genome Project.This study is a comparative characterization of LD in several human populations that will aid in understanding genomic evolution. Regions of the human genome that show high levels of LD in several ethnically diverse populations are likely to contain genes experiencing selection in the human species. Discovering genes which have experienced selection is relevant to the study of disease and aids in understanding human biological history. Knowledge about how LD depends on demography will aid in deciding which populations are appropriate to use for LD mapping of genes responsible for complex diseases and traits.