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Differential methylation between ethnic sub-groups reflects the effect of genetic ancestry and environmental exposures.

ABSTRACT: Populations are often divided categorically into distinct racial/ethnic groups based on social rather than biological constructs. Genetic ancestry has been suggested as an alternative to this categorization. Herein, we typed over 450,000 CpG sites in whole blood of 573 individuals of diverse Hispanic origin who also had high-density genotype data. We found that both self-identified ethnicity and genetically determined ancestry were each significantly associated with methylation levels at 916 and 194 CpGs, respectively, and that shared genomic ancestry accounted for a median of 75.7% (IQR 45.8% to 92%) of the variance in methylation associated with ethnicity. There was a significant enrichment (p=4.2×10-64) of ethnicity-associated sites amongst loci previously associated environmental exposures, particularly maternal smoking during pregnancy. We conclude that differential methylation between ethnic groups is partially explained by the shared genetic ancestry but that environmental factors not captured by ancestry significantly contribute to variation in methylation.

SUBMITTER: Galanter JM

PROVIDER: S-EPMC5207770 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Differential methylation between ethnic sub-groups reflects the effect of genetic ancestry and environmental exposures.

Galanter Joshua M JM Gignoux Christopher R CR Oh Sam S SS Torgerson Dara D Pino-Yanes Maria M Thakur Neeta N Eng Celeste C Hu Donglei D Huntsman Scott S Farber Harold J HJ Avila Pedro C PC Brigino-Buenaventura Emerita E LeNoir Michael A MA Meade Kelly K Serebrisky Denise D Rodríguez-Cintrón William W Kumar Rajesh R Rodríguez-Santana Jose R JR Seibold Max A MA Borrell Luisa N LN Burchard Esteban G EG Zaitlen Noah N

eLife 20170103

Populations are often divided categorically into distinct racial/ethnic groups based on social rather than biological constructs. Genetic ancestry has been suggested as an alternative to this categorization. Herein, we typed over 450,000 CpG sites in whole blood of 573 individuals of diverse Hispanic origin who also had high-density genotype data. We found that both self-identified ethnicity and genetically determined ancestry were each significantly associated with methylation levels at 916 and ...[more]

PMID: 28044981

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Dataset Information

Differential methylation between ethnic sub-groups reflects the effect of genetic ancestry and environmental exposures.

Publications

Differential methylation between ethnic sub-groups reflects the effect of genetic ancestry and environmental exposures.

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