Table 4.
Within-twin-pair association estimates between DNA methylation-based risk factors and conventional risk factors.
| Associationsa | All twin pairs | Monozygotic twin pairs | Dizygotic twin pairs | P for heterogeneity | |||
|---|---|---|---|---|---|---|---|
| β (95% CI) | P | β (95% CI) | P | β (95% CI) | P | ||
| Horvath clock | |||||||
| Body mass index | 6.26 (1.65, 10.87) | 8.8E-03 | 5.92 (−0.79, 12.62) | 0.09 | 6.48 (−0.01, 12.97) | 0.05 | 0.87 |
| Age at menarche | 0.24 (−0.40, 0.87) | 0.47 | 0.25 (−0.86, 1.36) | 0.66 | 0.23 (−0.60, 1.07) | 0.59 | 0.72 |
| Ever smoking | 1.09 (−0.53, 2.72) | 0.19 | 0.89 (−1.25, 3.03) | 0.42 | 1.27 (−1.19, 3.73) | 0.32 | 0.95 |
| Levine clock | |||||||
| Body mass index | 4.70 (−0.76, 10.15) | 0.09 | 4.65 (−3.33, 12.62) | 0.26 | 4.81 (−2.85, 12.47) | 0.22 | 0.84 |
| Pack-years of smoking | 0.61 (−0.60, 1.81) | 0.33 | 0.41 (−1.03, 1.84) | 0.59 | 0.87 (−1.47, 3.20) | 0.49 | 0.69 |
| Alcohol drinking | 0.50 (−1.50, 2.50) | 0.63 | 0.31 (−2.61, 3.23) | 0.83 | 0.61 (−2.23, 3.45) | 0.68 | 0.92 |
| Ever smoking | 1.21 (−0.72, 3.14) | 0.22 | 0.70 (−1.84, 3.25) | 0.59 | 1.63 (−1.27, 4.54) | 0.27 | 0.84 |
| Genome-wide average DNA methylationb | |||||||
| Number of live births | 0.01 (−0.13, 0.14) | 0.93 | 0.01 (−0.20, 0.22) | 0.94 | −0.001 (−0.21, 0.20) | 0.99 | 0.80 |
| Age at first live birth | −0.001 (−0.01, 0.01) | 0.96 | 0.001 (−0.02, 0.02) | 0.82 | −0.01 (−0.02, 0.01) | 0.46 | 0.53 |
| Ever smoking | −0.05 (−0.14, 0.04) | 0.28 | 0.01 (−0.13, 0.14) | 0.93 | −0.10 (−0.23, 0.03) | 0.14 | 0.26 |
aThe number of pairs included in the analysis for all twin pairs, monozygotic twin pairs and dizygotic twin pairs was 105, 53 and 52 for age at first live birth, 132, 66 and 66 for body mass index, age at menarche, smoking and alcohol drinking, 26, 15 and 11 for pack-years of smoking, and 105, 52 and 52 for number of live births; bValues are reported as percentage methylation.