Table 2.
Modelling results for the overall DNA methylation correlation as a function of twin pair cohabitation history
| Twin pair | Intercept α |
Increasing rate β1 |
Decreasing rate β2 |
|||
|---|---|---|---|---|---|---|
| Estimate (95% CI) | P | Estimate (95% CI) | P | Estimate (95% CI) | P | |
| Main analysis | ||||||
| MZ pairs | -0.038 (-0.114, 0.038) | 0.33 | 0.162 (0.121, 0.204) | 2.8 × 10−14 | -0.026 (-0.033, -0.019) | 1.5 × 10−12 |
| DZ pairs | -0.075 (-0.150, -0.0003) | 0.05 | 0.132 (0.071, 0.192) | 2.0 × 10−5 | -0.027 (-0.043, -0.011) | 8.1 × 10−4 |
| MZ & DZ pairs combined | -0.071 (-0.174, 0.033) | 0.18 | 0.159 (0.099, 0.219) | 2.0 × 10−7 | -0.025 (-0.036, -0.014) | 8.0 × 10−6 |
| Sensitivity analysis: Observed twin pair age used in modelling (NTR age simulated) | ||||||
| MZ pairs | -0.025 (-0.070, 0.019) | 0.27 | 0.149 (0.118, 0.181) | <1 × 10−15 | -0.020 (-0.031, -0.010) | 2.2 × 10−4 |
| DZ pairs | -0.062 (-0.114, -0.009) | 0.02 | 0.119 (0.061, 0.177) | 6.7 × 10−5 | -0.023 (-0.039, -0.007) | 6.2 × 10−3 |
| MZ & DZ pairs combined | -0.057 (-0.127, 0.014) | 0.12 | 0.146 (0.097, 0.195) | 5.1 × 10−9 | -0.020 (-0.033, -0.007) | 3.1 × 10−3 |
| Sensitivity analysis: Observed twin pair age used in modelling (NTR age assumed to be the average) | ||||||
| MZ pairs | -0.029 (-0.081, 0.023) | 0.28 | 0.156 (0.127, 0.185) | <1 × 10−15 | -0.025 (-0.032, -0.018) | 2.4 × 10−11 |
| DZ pairs | -0.065 (-0.119, -0.011) | 0.02 | 0.124 (0.071, 0.177) | 5.2 × 10−6 | -0.026 (-0.042, -0.010) | 1.7 × 10−3 |
| MZ & DZ pairs combined | -0.060 (-0.138, 0.017) | 0.13 | 0.152 (0.105, 0.199) | 2.3 × 10−10 | -0.024 (-0.035, -0.013) | 1.9 × 10−5 |
| Sensitivity analysis: Observed twin pair age used in modelling (NTR data excluded) | ||||||
| MZ pairs | -0.031 (-0.086, 0.025) | 0.28 | 0.159 (0.129, 0.189) | <1 × 10−15 | -0.025 (-0.032, -0.019) | 9.0 × 10−14 |
| DZ pairs | -0.078 (-0.148, -0.008) | 0.03 | 0.142 (0.096, 0.188) | 1.9 × 10−9 | -0.027 (-0.038, -0.016) | 1.2 × 10−6 |
| MZ & DZ pairs combined | -0.066 (-0.153, 0.022) | 0.14 | 0.160 (0.112, 0.209) | 1.5 × 10−10 | -0.025 (-0.034, -0.016) | 5.9 × 10−8 |
| Sensitivity analysis: Median correlation of the investigated sites used in modelling | ||||||
| MZ pairs | -0.069 (-0.131, -0.007) | 0.03 | 0.143 (0.099, 0.187) | 2.6 × 10−10 | -0.020 (-0.031, -0.009) | 5.3 × 10−4 |
| DZ pairs | -0.072 (-0.133, -0.012) | 0.02 | 0.116 (0.060, 0.173) | 5.8 × 10−5 | -0.024 (-0.039, -0.008) | 3.7 × 10−3 |
| MZ & DZ pairs combined | -0.078 (-0.151, -0.004) | 0.04 | 0.136 (0.083, 0.189) | 5.0 × 10−7 | -0.020 (-0.033, -0.008) | 1.7 × 10−3 |
MZ – monozygotic; DZ – dizygotic; CI – confidence interval; NTR – Netherlands Twin Register.