TY - JOUR TI - Differential methylation between ethnic sub-groups reflects the effect of genetic ancestry and environmental exposures AU - Galanter, Joshua M AU - Gignoux, Christopher R AU - Oh, Sam S AU - Torgerson, Dara AU - Pino-Yanes, Maria AU - Thakur, Neeta AU - Eng, Celeste AU - Hu, Donglei AU - Huntsman, Scott AU - Farber, Harold J AU - Avila, Pedro C AU - Brigino-Buenaventura, Emerita AU - LeNoir, Michael A AU - Meade, Kelly AU - Serebrisky, Denise AU - Rodríguez-Cintrón, William AU - Kumar, Rajesh AU - Rodríguez-Santana, Jose R AU - Seibold, Max A AU - Borrell, Luisa N AU - Burchard, Esteban G AU - Zaitlen, Noah A2 - Nordborg, Magnus VL - 6 PY - 2017 DA - 2017/01/03 SP - e20532 C1 - eLife 2017;6:e20532 DO - 10.7554/eLife.20532 UR - https://doi.org/10.7554/eLife.20532 AB - 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. KW - methylation KW - epigenetics KW - ethnicity KW - Latinos JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -