Population Stratification in Genetic Association Studies

Jacklyn N. Hellwege1, Jacob M. Keaton1, Ayush Giri1, Xiaoyi Gao2, Digna R. Velez Edwards3, Todd L. Edwards1

1 Vanderbilt Genetics Institute, Division of Epidemiology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, 2 Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, Illinois, 3 Vanderbilt Genetics Institute, Department of Obstetrics and Gynecology, Vanderbilt University Medical Center, Nashville, Tennessee
Publication Name:  Current Protocols in Human Genetics
Unit Number:  Unit 1.22
DOI:  10.1002/cphg.48
Online Posting Date:  October, 2017
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Abstract

Population stratification (PS) is a primary consideration in studies of genetic determinants of human traits. Failure to control for PS may lead to confounding, causing a study to fail for lack of significant results, or resources to be wasted following false‐positive signals. Here, historical and current approaches for addressing PS when performing genetic association studies in human populations are reviewed. Methods for detecting the presence of PS, including global and local ancestry methods, are described. Also described are approaches for accounting for PS when calculating association statistics, such that measures of association are not confounded. Many traits are being examined for the first time in minority populations, which may inherently feature PS. © 2017 by John Wiley & Sons, Inc.

Keywords: admixture; admixture mapping; association confounding; global ancestry; local ancestry; population stratification

     
 
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Table of Contents

  • Key Concepts
  • Quantifying Population Stratification
  • Strategy
  • Conclusion
  • Literature Cited
  • Figures
  • Tables
     
 
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Materials

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Figures

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Literature Cited

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