title: Social factors and leukocyte DNA methylation of repetitive sequences: the multi-ethnic study of atherosclerosis.
abstract: Epigenetic changes are a potential mechanism contributing to race/ethnic and socioeconomic disparities in health. However, there is scant evidence of the race/ethnic and socioeconomic patterning of epigenetic marks. We used data from the Multi-Ethnic Study of Atherosclerosis Stress Study (N = 988) to describe age- and gender-independent associations of race/ethnicity and socioeconomic status (SES) with methylation of Alu and LINE-1 repetitive elements in leukocyte DNA. Mean Alu and Line 1 methylation in the full sample were 24% and 81% respectively. In multivariable linear regression models, African-Americans had 0.27% (p<0.01) and Hispanics 0.20% (p<0.05) lower Alu methylation than whites. In contrast, African-Americans had 0.41% (p<0.01) and Hispanics 0.39% (p<0.01) higher LINE-1 methylation than whites. These associations remained after adjustment for SES. In addition, a one standard deviation higher wealth was associated with 0.09% (p<0.01) higher Alu and 0.15% (p<0.01) lower LINE-1 methylation in age- and gender-adjusted models. Additional adjustment for race/ethnicity did not alter this pattern. No associations were observed with income, education or childhood SES. Our findings, from a large community-based sample, suggest that DNA methylation is socially patterned. Future research, including studies of gene-specific methylation, is needed to understand better the opposing associations of Alu and LINE-1 methylation with race/ethnicity and wealth as well as the extent to which small methylation changes in these sequences may influence disparities in health.
authors: Social Epidemiology, Indian Institute of Technology Gandhinagar, Ahmedabad, Gujarat, India. Malavika@iitgn.ac.in
authors: Malavika A
authors: MA
authors: Subramanyam
authors: Ana V
authors: AV
authors: Diez-Roux
authors: J Richard
authors: JR
authors: Pilsner
authors: Eduardo
authors: E
authors: Villamor
authors: Kathleen M
authors: KM
authors: Donohue
authors: Yongmei
authors: Y
authors: Liu
authors: Nancy S
authors: NS
authors: Jenny
mesh_terms: D001741:Black or African American / Q000235:genetics; D000368:Aged; D000369:Aged, 80 and over; D020087:Alu Elements / Q000235:genetics; D050197:Atherosclerosis / Q000208:ethnology / Q000209:etiology / Q000235:genetics*; D019175:DNA Methylation / Q000235:genetics; D005006:Ethnicity / Q000235:genetics*; D005260:Female; D006630:Hispanic or Latino / Q000235:genetics; D006801:Humans; D007962:Leukocytes / Q000378:metabolism*; D020084:Long Interspersed Nucleotide Elements; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D044465:White People / Q000235:genetics