TABLE 5.
Sex and zygosity for discordant twins in this series and literature series
| Sex |
Zygosity |
||||||
|---|---|---|---|---|---|---|---|
| N | M | F | UNK | DZ | MZ | UZ | |
| This series | |||||||
| MCD | 34 | 18 | 16 | 0 | 8 | 17 | 9 |
| CBLH-DWM | 12 | 8 | 4 | 0 | 6 | 4 | 2 |
| BRD | 10 | 5 | 5 | 0 | 5 | 1 | 4 |
|
| |||||||
| Total | 56 | 31 | 25 | 0 | 19 | 22 | 15 |
|
| |||||||
| Literature series | |||||||
| MCD | 14 | 7 | 7 | 0 | 0 | 14 | 0 |
| CBLH-DWM | 16 | 3 | 6 | 7 | 0 | 14 | 2 |
| BRD | 18 | 14 | 4 | 0 | 1 | 17 | 0 |
|
| |||||||
| Total | 48 | 24 | 17 | 7 | 1 | 45 | 2 |
Note: N = 56 subjects with seven affected co-twins excluded. References for literature twin cohort provided in Supplementary Tables S2–S4. For 7/56 proband twins, the co-twin was concordant for a brain malformation or disruption, but discordant for severity; the more severely affected co-twin was always selected as the proband twin.
Abbreviations: BRD, brain disruptions including hydranencephaly–porencephaly; CBLH, cerebellar hypoplasia; DWM, Dandy–Walker malformation; DZ, dizygotic twins; MCD, malformation of cortical development; MZ, monozygotic twins; UNK, unknown sex; UZ, unknown zygosity.