No. patients studied | No. patients affected | ICR1 methylation | ICR2 methylation | Notes of interest | Refs | ||
9 SRS | 5/9 SRS | Hypomethylation of H19 DMD/ICR1 | Normal | Unaffected monozygotic twin; no hypomethylation in fibroblasts | 53 | ||
3 Con | |||||||
1 BWS | |||||||
3 SRS | 2/3 SRS | Examined H19 promoter only.Complete hypomethylation of two SRS patients | Normal | One additional SRS patient had no methylation aberration | 69 | ||
7 IUGR | |||||||
2 Con | 7/7 IUGR | ||||||
2 BWS | |||||||
51 SRS | 16/51 SRS | Hypomethylation H19 DMD/ICR1: MI 20–37% | Normal | 80% of patients with hypomethylation defects had body asymmetry | 70 | ||
58 SRS | 37/58 SRS | H19 DMD/ICR1: MI 1–39% | Normal | Only affects SRS patientsNormal IGFII serum in 82 patients | 64 | ||
69 SGA (Non-SRS) | |||||||
1 SRS | 1 SRS | No methylation defects noted | Maternal ICR2 duplication | mUPD 7 excluded; paternally expressed KCNQ1OT1 including maternally expressed KCNQ1, CDKNIC, SLC22A8, PHLDA2 | 71 |
BWS, Beckwith–Wiedemann syndrome; Con, controls; IUGR, intrauterine growth restriction; MI, methylation index; SGA, small for gestational age; SRS, Silver–Russell syndrome.