Table 2.
Genome-wide DNA methylation by tissue
| Chorionic villi | Kidney | Spinal cord | Brain | Muscle | ||
|---|---|---|---|---|---|---|
| Median array average ± SD (n) | Control | 0.432 ± 0.006 (16) | 0.471 ± 0.004 (16) | 0.486 ± 0.002 (9) | 0.486 ± 0.004 (11) | 0.484 ± 0.004 (13) |
| Spina bifida | 0.427 ± 0.007 (22)** | 0.470 ± 0.003 (20) | 0.481 ± 0.004 (17)* | 0.482 ± 0.004 (9) | 0.484 ± 0.003 (10) | |
| Anencephaly | 0.425 ±0.007 (14)* | 0.468 ± 0.003 (8) | 0.485 ± 0.003 (6) | – | 0.484 ±0.003 (8) | |
| Median % LINE1 DNAm ± SD (n) | Control | 55.8 ± 3.8 (16) | 79.2 ± 1.5 (16) | 79.9 ± 1.5 (9) | 81.5 ± 2.0 (11) | 80.3 ± 1.4 (13) |
| Spina bifida | 56.7 ± 3.0 (22) | 78.3 ± 2.1 (20) | 80.9 ±1.7 (17) | 83.2 ± 1.4 (9) | 80.9 ± 1.6 (10) | |
| Anencephaly | 55.0 ± 2.9 (14) | 78.5 ± 1.4 (8) | 79.7 ± 1.7 (6) | – | 80.5 ± 1.4 (8) | |
| Median % Alu DNAm ± SD (n) | Control | 22.6 ±1.1 (16) | 24.7 ± 1.2 (16) | 25.0 ± 0.9 (9) | 25.6 ± 1.6 (11) | 24.2 ±1.0 (13) |
| Spina bifida | 22.3 ± 1.1 (22) | 24.8 ± 1.5 (20) | 26.1 ± 1.6 (17) | 25.4 ± 1.2 (9) | 25.0 ± 2.2 (10) | |
| Anencephaly | 22.8 ± 1.3 (14) | 24.1 ± 2.1 (8) | 25.4 ± 0.9 (6) | – | 24.5 ± 0.6 (8) | |
p values based on comparison of spina bifida to controls or anencephaly to controls. *p < 0.05 based on 1000 permutations of Mann–Whitney test, **p < 0.01 based on 1000 permutations of Mann–Whitney test. SD standard deviation