Table 2.
Case Wise Concordances of VMI Abnormalities in MZ and DZ Twins
| VMI Abnormality | No. of Twin Pairs Concordant for Trait | No. of Twin Pairs Discordant for Trait | Concordance | Risk Ratio MZ/DZ |
|---|---|---|---|---|
| ERM | ||||
| MZ | 83 | 188 | 0.47 | 1.74 |
| DZ | 33 | 180 | 0.27 | |
| FTMH | ||||
| MZ | 0 | 0 | − | − |
| DZ | 0 | 1 | − | |
| LMH | ||||
| MZ | 1 | 21 | − | − |
| DZ | 1 | 15 | − | |
| PVD | ||||
| MZ | 88 | 193 | 0.48 | 1.26 |
| DZ | 56 | 186 | 0.38 | |
| VMA | ||||
| MZ | 45 | 158 | 0.36 | 1.64 |
| DZ | 23 | 1623 | 0.22 | |
| VMT | − | |||
| MZ | 1 | 21 | − | |
| DZ | 0 | 18 | − |
DZ, dizygotic twin pairs; ERM, epiretinal membrane; FTMH, full thickness macular hole; LMH, lamellar macular hole; MZ, monozygotic twin pairs; PVD, posterior vitreous detachment; VMA, vitreomacular adhesion; VMT, vitreomacular traction.