Table 1 Distribution of low, intermediate and highly methylated DNA methylation sites between different genomic elements in NEC and non-NEC ileum tissues
Feature | Methylation | Ileum | ||||
|---|---|---|---|---|---|---|
Percent | NEC (%)a | Non-NEC (%)a | Chi-square2b | df | p | |
Promoter |  < 20 | 37,570 (21.3) | 37,809 (21.4) | 5.1 | 2 | 0.079 |
20–80 | 67,544 (38.2) | 67,963 (38.5) | ||||
 > 80 | 71,628 (40.5) | 70,970 (40.2) | ||||
Exonic | < 20 | 11,252 (4.7) | 11,276 (4.7) | 83.9 | 2 | < 0.0001 |
20–80 | 105,227 (43.6) | 108,315 (44.9) | ||||
> 80 | 124,986 (51.8) | 121,874 (50.5) | ||||
Intronic | < 20 | 83,095 (1.9) | 84,504 (1.9) | 2270 | 2 | < 0.0001 |
20–80 | 1,880,459 (42.3) | 1,949,492 (43.8) | ||||
> 80 | 2,483,522 (55.8) | 2,413,080 (54.3) | ||||
CpG Island | < 20 | 14,248 (45.5) | 14,297 (45.6) | 0.32 | 2 | 0.85 |
20–80 | 6478 (20.7) | 6496 (20.7) | ||||
> 80 | 10,611 (33.9) | 10,544 (33.6) | ||||
CpG Shore | < 20 | 55,456 (15.9) | 55,885 (16.0) | 9.49 | 2 | 0.0087 |
20–80 | 125,323 (35.9) | 124,102 (35.6) | ||||
> 80 | 168,110 (48.2) | 168,902 (48.4) | ||||
Enhancer | < 20 | 895 (7.6) | 910 (7.7) | 2.55 | 2 | 0.28 |
20–80 | 5807 (49.4) | 5913 (50.3) | ||||
> 80 | 5047 (43.0) | 4926 (41.9) | ||||
Intergenic | < 20 | 80,112 (1.7) | 82,289 (1.7) | 7668 | 2 | < 0.0001 |
20–80 | 2,462,179 (51.2) | 2,595,021 (54.0) | ||||
> 80 | 2,264,520 (47.1) | 2,129,501 (44.3) | ||||
CpG Island + CpG Shore | < 20 | 69,704 (18.3) | 70,182 (18.5) | 8.62 | 2 | 0.014 |
20–80 | 131,801 (34.7) | 130,598 (34.3) | ||||
> 80 | 178,721 (47.0) | 179,446 (47.2) | ||||
Exons + Introns | < 20 | 94,347 (2.0) | 95,780 (2.0) | 2349 | 2 | < 0.0001 |
20–80 | 1,985,686 (42.4) | 2,057,807 (43.9) | ||||
> 80 | 2,608,508 (55.6) | 2,534,954 (54.1) | ||||
All | < 20 | 205,779 (2.1) | 208,548 (2.2) | 12,306 | 2 | < 0.0001 |
20–80 | 4,378,720 (45.3) | 4,618,095 (47.8) | ||||
> 80 | 5,074,456 (52.5) | 4,832,312 (50.0) | ||||