Table 2.
Within-study familial correlations in DNAm age
| Studya | Type of pairs | Number of pairs | Mean age | Correlation (95% CI) | P | P for MZ versus DZ |
|---|---|---|---|---|---|---|
| PETS EPIC | MZ | 23 | 0 | 0.18 (− 0.28 to 0.57) | 0.45 | 0.57 |
| DZ | 22 | 0 | 0.01 (− 0.35 to 0.36) | 0.98 | ||
| MZ and DZ | 45 | 0 | 0.15 (− 0.22 to 0.34) | 0.64 | ||
| PETS 27K | MZ | 22 | 0 | 0.35 (− 0.04 to 0.64) | 0.85 | 0.69 |
| DZ | 11 | 0 | 0.00 (− 0.46 to 0.46) | 0.09 | ||
| MZ and DZ | 33 | 0 | 0.18 (− 0.15 to 0.47) | 0.76 | ||
| PETS 450K birth | MZ | 9 | 0 | − 0.05 (− 0.51 to 0.43) | 0.09 | 0.29 |
| DZ | 5 | 0 | 0.62 (0.01 to 0.89) | 0.99 | ||
| MZ and DZ | 14 | 0 | − 0.08 (− 0.54 to 0.41) | 0.29 | ||
| PETS 450K 18 months | MZ | 6 | 1.5 | − 0.06 (− 0.62 to 0.55) | 0.87 | 0.58 |
| DZ | 4 | 1.5 | − 0.52 (− 0.91 to 0.40) | 0.31 | ||
| MZ and DZ | 10 | 1.5 | − 0.12 (− 0.62 to 0.46) | 0.71 | ||
| BSGS | MZ | 67 | 13.8 | 0.69 (0.63 to 0.74) | < 0.001 | < 0.001 |
| DZ | 111 | 13.2 | 0.35 (0.20 to 0.48) | < 0.001 | ||
| Siblings | 260 | 14.0 | 0.32 (0.20 to 0.42) | < 0.001 | ||
| Parent–offspring | 363 | 13.4 | 0.15 (0.02 to 0.27) | 0.02 | ||
| Spouses | 59 | 46.6 | − 0.01 (− 0.25 to 0.24) | 0.96 | ||
| E-Risk | MZ | 426 | 18.0 | 0.46 (0.40 to 0.52) | < 0.001 | 0.28 |
| DZ | 306 | 18.0 | 0.40 (0.33 to 0.47) | < 0.001 | ||
| MZ and DZ | 732 | 18.0 | 0.43 (0.39 to 0.48) | < 0.001 | ||
| DTR younger adults | MZ | 73 | 33.1 | 0.62 (0.52 to 0.70) | < 0.001 | − |
| AMDTSS | MZ | 66 | 55.6 | 0.43 (0.26 to 0.58) | < 0.001 | 0.20 |
| DZ | 66 | 57.0 | 0.24 (0.04 to 0.42) | 0.02 | ||
| MZ and DZ | 132 | 56.3 | 0.32 (0.18 to 0.45) | < 0.001 | ||
| Siblings | 552 | 56.4 | 0.12 (0.02 to 0.22) | 0.02 | ||
| TwinsUK | MZ | 33 | 55.3 | 0.23 (− 0.03 to 0.46) | 0.09 | 0.41 |
| DZ | 43 | 59.2 | 0.04 (− 0.33 to 0.39) | 0.85 | ||
| MZ and DZ | 76 | 57.5 | 0.12 (− 0.07 to 0.37) | 0.17 | ||
| MuTHER | MZ | 93 | 58.4 | 0.54 (0.44 to 0.63) | < 0.001 | 0.08 |
| DZ | 153 | 56.6 | 0.37 (0.25 to 0.48) | < 0.001 | ||
| MZ and DZ | 246 | 57.3 | 0.44 (0.36 to 0.52) | < 0.001 | ||
| DTR older adults | MZ | 77 | 63.2 | 0.55 (0.43 to 0.65) | < 0.001 | − |
| OATS | MZ | 108 | 71.2 | 0.40 (0.26 to 0.53) | < 0.001 | − |
| LSADT 1997 | MZ | 18 | 76.3 | 0.04 (− 0.66 to 0.70) | 0.93 | 0.36 |
| DZ | 25 | 76.2 | 0.39 (0.14 to 0.60) | < 0.001 | ||
| MZ and DZ | 43 | 76.2 | 0.34 (0.09 to 0.55) | 0.01 | ||
| LSADT 2007 | MZ | 18 | 86.2 | 0.41 (0.05 to 0.68) | 0.04 | 0.95 |
| DZ | 25 | 86.1 | 0.40 (0.11 to 0.62) | 0.01 | ||
| MZ and DZ | 43 | 86.1 | 0.40 (0.17 to 0.59) | < 0.001 | ||
| MCCS | Spouses | 62 | 60.1 | 0.12 (− 0.12 to 0.35) | 0.33 | − |
MZ monozygotic twin, DZ dizygotic twin, CI confidence interval
aStudies—PETS Peri/postnatal Epigenetic Twins Study, including three datasets measured using the 27K array, 450K array (at two points: at birth and age 18 months), and EPIC array, respectively; BSGS Brisbane System Genetics Study; E-Risk Environmental Risk Longitudinal Twin Study, DTR Danish Twin Registry, in two groups: younger and older adults, AMDTSS Australian Mammographic Density Twins and Sisters Study, MuTHER Multiple Tissue Human Expression Resource Study, OATS Older Australian Twins Study, LSADT Longitudinal Study of Aging Danish Twins, with samples collected at years 1997 and 2007, respectively, MCCS Melbourne Collaborative Cohort Study