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Ancestral heterogeneity in a biethnic stroke population.

ABSTRACT: To test for and characterize heterogeneity in ancestral contributions to individuals among a population of Mexican American (MA) and non-Hispanic white (NHW) stroke/transient ischemic attack (TIA) cases, data from a community-based stroke surveillance study in south Texas were used. Strokes/TIA cases were identified (2004-2006) with a random sample asked to provide blood. Race-ethnicity was self-reported. Thirty-three ancestry informative markers were genotyped and individual genetic admixture estimated using maximum likelihood methods. Three hypotheses were tested for each MA using likelihood ratio tests: (1) H(0) : ?i = 0 (100% Native American), (2) H(0) : ?i = 1.00 (100% European), (3) H(0) : ?i = 0.59 (average European). Among 154 self-identified MAs, estimated European ancestry varied from 0.26 to 0.98, with an average of 0.59 (SE = 0.014). We rejected hypothesis 1 for every MA and rejected hypothesis 2 for all but two MAs. We rejected hypothesis 3 for 40 MAs (20 < 59%, 20 > 59%). Among 84 self-identified NHWs, the estimated fraction of European ancestry ranged from 0.83 to 1.0, with an average of 0.97 (SE = 0.014). Self-identified MAs, and to a lesser extent NHWs, from an established bi-ethnic community were heterogeneous with respect to genetic admixture. Researchers should not use simple race-ethnic categories as proxies for homogeneous genetic populations when conducting gene mapping and disease association studies in multi-ethnic populations.

SUBMITTER: Lisabeth LD

PROVIDER: S-EPMC3133673 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature

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Ancestral heterogeneity in a biethnic stroke population.

Lisabeth Lynda D LD Morgenstern Lewis B LB Burke David T DT Sun Yan V YV Long Jeffrey C JC

Annals of human genetics 20110701 4

To test for and characterize heterogeneity in ancestral contributions to individuals among a population of Mexican American (MA) and non-Hispanic white (NHW) stroke/transient ischemic attack (TIA) cases, data from a community-based stroke surveillance study in south Texas were used. Strokes/TIA cases were identified (2004-2006) with a random sample asked to provide blood. Race-ethnicity was self-reported. Thirty-three ancestry informative markers were genotyped and individual genetic admixture e ...[more]

PMID: 21668907

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Dataset Information

Ancestral heterogeneity in a biethnic stroke population.

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Ancestral heterogeneity in a biethnic stroke population.

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