Table 4 Findings from nine studies investigating the timing and/or duration of socioeconomic position and DNA methylation
From: Associations between indicators of socioeconomic position and DNA methylation: a scoping review
References | DNAm approach | SEP exposure age(s)a | Reported age(s) at DNAmb | Key findingsc |
|---|---|---|---|---|
Sensitive period of child SEP on child or adult DNAm | Â | Â | Â | Â |
Dunn et al. [71] | EWAS | Child (prospectively measured 5×) | 7 | Neighborhood disadvantage and financial stress associated with 10 and 9 CpGs (pbonf < 1 × 10−7), respectively, with 8 and 2 of these differentially methylated sites relating to the developmental timing of SEP exposure in very early childhood (birth to age 2) |
Lam et al. [72] | EWAS | Child (retrospectively measured) + Adult | Mdn = 33.04 | Low child SEP associated with 3 CpGs (q < 0.25), while current (adult) SEP did not |
Borghol et al. [69] | EWAS | Child (prospectively measured) + Adult | 42 + 45 | Child SEP associated with 1252 gene promoters, while adult SEP associated with 545 (q ≤ 0.2). Child and adult SEP-associated promoter sets overlapped at 63 promoters |
Sensitive period of adult SEP on adult DNAm | Â | Â | Â | Â |
Stringhini et al. [61] | Candidate Gene | Child (retrospectively measured) + Adult | ~ 45–63 | Current (adult) SEP associated with 41 CpGs in 10 genes (q ≤ 5.10 × 10−3), while child SEP did not have any associations when FDR procedure was applied |
Subramanyam et al. [46] | Global DNAm | Child (retrospectively measured) + Adult | M = 61 | One SD higher adult wealth associated, on average, with 0.09% higher Alu (p < 0.01) and 0.15% lower LINE-1 DNAm (p < 0.01), while adult income, adult education, and child SEP did not associate with LINE-1 or Alu DNAm |
Sensitive periods of both child and adult SEP on adult DNAm | Â | Â | Â | Â |
Tehranifar et al. [47] | Global DNAm | Child (prospectively measured) + Adult | M = 43 | For child SEP, lower maternal education and lower family income associated with higher mean levels of Sat-2 DNAm (p < 0.05 and p < 0.10, respectively); single-parent family structure compared to two-parent structure associated with higher Alu methylation (p < 0.05). Adult income associated with increased LINE-1 methylation (p < 0.05) |
Suderman et al. [77] | EWAS | Child (prospectively measured) + Adult | 45 | Child SEP associated with 2 CpGs, while adult SEP associated with 3 CpGs (q < 0.2) in whole blood or LCLs. None of the SEP-associated CpGs were shared between child and adult SEP |
Needham et al. [59] | Candidate Gene | Child (retrospectively measured) + Adult | M = 69.55 | Low child SEP associated with DNAm in 3 stress- and 2 inflammation-related genes, whereas low adult SEP primarily associated with DNAm in inflammation-related genes (5 inflammation- and 1 stress-related gene; all p < 0.05; q < 0.20). SEP-DNAm associations between child and adult SEP overlapped at 3 of 9 total candidate genes |
Effects of life-course SEP trajectories on adult DNAm | Â | Â | Â | Â |
McDade et al. [75] | EWAS | Child + Adult (prospectively measured 4×) | M = 20.9 | Persistently low SEP from infancy to young adulthood associated with 2546 CpGs (q < 0.05), compared to persistently high SEP. One CpG associated with DNAm for upward SEP mobility group and no sites associated with the downward mobility group (q < 0.05) |
Stringhini et al. [61] | Candidate Gene | Child (retrospectively measured) + Adult | ~ 45–63 | Persistently low SEP from childhood to adulthood associated with 12 CpGs in 6 genes, compared to persistently high SEP, while downward SEP and upward SEP mobility groups associated with 5 CpGs in 4 genes and 1 CpG in 1 gene, respectively (q ≤ 1.49 × 10−3) |
Needham et al. [59] | Candidate Gene | Child (retrospectively measured) + Adult | M = 69.55 | Persistently low SEP from childhood to adulthood associated with DNAm in 5 genes, upward SEP mobility associated with 1 gene, and downward mobility associated with 2 genes in comparison with persistently high SEP (p < 0.05; q < 0.20) |