Table 1.
Blood DNA methylation levels (percentage of 5-methylcytosine) in 1,515 visits, the Normative Aging Study, 1999–2009.
| Gene and position | n | DNA methylation (mean ± SD) | Percentile | ||
|---|---|---|---|---|---|
| 5th | 50th | 95th | |||
| CRAT | 1,411 | ||||
| Position 1 | 1.7 ± 0.6 | 1.0 | 1.7 | 2.6 | |
| Position 2 | 4.7 ± 1.6 | 2.4 | 4.6 | 7.7 | |
| Mean | 3.2 ± 1.0 | 1.7 | 3.2 | 5.1 | |
| F3 | 1,273 | ||||
| Position 1 | 1.5 ± 1.8 | 0.0 | 1.2 | 4.2 | |
| Position 2 | 1.6 ± 1.9 | 0.0 | 1.2 | 4.6 | |
| Position 3 | 3.0 ± 2.2 | 0.0 | 2.5 | 6.9 | |
| Position 4 | 1.4 ± 1.6 | 0.0 | 1.1 | 3.9 | |
| Position 5 | 4.5 ± 2.6 | 0.0 | 4.2 | 8.5 | |
| Mean | 2.4 ± 1.3 | 0.9 | 2.2 | 4.5 | |
| GCR | 1,283 | ||||
| Position 1 | 47 ± 6 | 36 | 47 | 55 | |
| ICAM | 1,173 | ||||
| Position 1 | 5.8 ± 2.3 | 2.9 | 5.5 | 10.3 | |
| Position 2 | 3.5 ± 2.2 | 1.7 | 3.0 | 9.2 | |
| Position 3 | 3.8 ± 2.0 | 1.7 | 3.3 | 7.3 | |
| Mean | 4.4 ± 1.8 | 2.3 | 4.0 | 8.1 | |
| IFN-γ | 1,460 | ||||
| Position 1 | 82 ± 6 | 72 | 84 | 90 | |
| Position 2 | 87 ± 5 | 80 | 88 | 93 | |
| Mean | 85 ± 5 | 76 | 86 | 91 | |
| IL6 | 1,469 | ||||
| Position 1 | 47 ± 12 | 27 | 47 | 66 | |
| Position 2 | 40 ± 11 | 22 | 40 | 58 | |
| Mean | 43 ± 10 | 26 | 44 | 62 | |
| iNOS | 1,017 | ||||
| Position 1 | 53 ± 8 | 39 | 53 | 66 | |
| Position 2 | 83 ± 9 | 65 | 85 | 97 | |
| Mean | 68 ± 7 | 55 | 69 | 79 | |
| OGG1 | 915 | ||||
| Position 1 | 2.1 ± 2.6 | 0.0 | 1.2 | 7.4 | |
| Position 2 | 2.9 ± 2.6 | 0.0 | 2.3 | 8.3 | |
| Position 3 | 2.2 ± 2.0 | 0.0 | 1.9 | 6.1 | |
| Position 4 | 2.0 ± 2.2 | 0.0 | 1.5 | 6.5 | |
| Mean | 2.3 ± 1.4 | 0.7 | 1.9 | 4.9 | |
| TLR2 | 1,172 | ||||
| Position 1 | 2.8 ± 1.8 | 0.0 | 2.5 | 6.1 | |
| Position 2 | 3.5 ± 2.0 | 0.0 | 3.3 | 7.1 | |
| Position 3 | 2.9 ± 2.0 | 0.0 | 2.6 | 6.3 | |
| Position 4 | 3.7 ± 2.1 | 0.0 | 3.4 | 7.3 | |
| Position 5 | 2.0 ± 1.9 | 0.0 | 1.8 | 5.6 | |
| Mean | 3.0 ± 1.3 | 1.2 | 2.7 | 5.4 | |