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Impact of Population Stratification on Family-Based Association in an Admixed Population.

ABSTRACT: Population substructure is a well-known confounder in population-based case-control genetic studies, but its impact in family-based studies is unclear. We performed population substructure analysis using extended families of admixed population to evaluate power and Type I error in an association study framework. Our analysis shows that power was improved by 1.5% after principal components adjustment. Type I error was also reduced by 2.2% after adjusting for family substratification. The presence of population substructure was underscored by discriminant analysis, in which over 92% of individuals were correctly assigned to their actual family using only 100 principal components. This study demonstrates the importance of adjusting for population substructure in family-based studies of admixed populations.

SUBMITTER: Mersha TB

PROVIDER: S-EPMC4434195 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Impact of Population Stratification on Family-Based Association in an Admixed Population.

Mersha T B TB Ding L L He H H Alexander E S ES Zhang X X Kurowski B G BG Pilipenko V V Kottyan L L Martin L J LJ Fardo D W DW

International journal of genomics 20150504

Population substructure is a well-known confounder in population-based case-control genetic studies, but its impact in family-based studies is unclear. We performed population substructure analysis using extended families of admixed population to evaluate power and Type I error in an association study framework. Our analysis shows that power was improved by 1.5% after principal components adjustment. Type I error was also reduced by 2.2% after adjusting for family substratification. The presence ...[more]

PMID: 26064873

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