Table III.
DNA CpG methylation in human oocytes at different stages of development with and without ovarian stimulation and IVM.
| Reference | gDMR | Methylation | No ovarian stimulation |
Ovarian stimulation, in vivo maturation |
Ovarian stimulation, IVM of GV |
||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Primary follicle | Pre-antral follicle | Antral follicle | GV | MI | MII | Arrested GV | Arrested MI | MII | |||
| Sato et al. (2007) | MEST | M | 50.0 | 57.0 | 91.6 | 55.6 (5/9) | 71.4 (5/7) | ||||
| PLAGL1 | M | 40.0 | 10.4 | 83.3 | |||||||
| KCNQ1OT1 | M | 55.5 | 66.6 | 87.5 | |||||||
| Geuns et al. (2007b) | KCNQ1OT1 | M | 100 (6/6) | 83.3 (5/6) | 100c (4/4) | ||||||
| Khoueiry et al. (2008) | KCNQ1OT1 | M | 67.8 (GV)a | 62.5 | 66.7 | 89.5 | 61.2 | 65.2 | 78.3 | ||
| 70.3 (MI)a | |||||||||||
| Geuns et al. (2003) | SNRPN | M | 100 (7/7) | 100 (3/3) | 100c (3/3) | ||||||
| El-Maarri et al. (2001) | SNRPN | M | 0b | ||||||||
| NDN | M | 33.3b | |||||||||
| Sato et al. (2007) | H19 | P | 28.2 | 33.4 | 12.5 | 0 (0/3) | 66.7 (2/3) | ||||
| Borghol et al. (2006) | H19 | P | 0 (0/5) | 24.3 | 13.8 | 16.7 | |||||
| Geuns et al. (2007a) | DLK1 | P | 0 (0/4) | 0 (0/6) | 0c (0/6) | ||||||
Methylation is depicted as the percentage of methylated alleles (greater-than two-third of DMR is methylated) of the total number of alleles analysed.
M, maternal; P, paternal.
If known, the number of methylated oocytes and the total number of oocytes are put in parentheses.
aGV and MI are obtained from non-stimulated patients with polycystic ovaries and after culture arrested in GV and MI.
bUnfertilized oocytes.
cMII obtained after culture of both GV and MI.