Table 1.
Sibling sex ratio in gender dysphoric adolescents and control subjects
| Group | Probands | Brothers | Sisters | Overall sex ratio | Sex ratio older sibs | Sex ratio younger sibs |
|---|---|---|---|---|---|---|
| GD boys | 94 | 89 (OB 48, YB 41) | 37 (OS 16, YS 21) | 241:100** | 300:100** | 195:100* |
| GD girls | 95 | 43 (OB 24, YB 19) | 56 (OS 22, YS 34) | 77:100 | 109:100 | 56:100 |
| Control boys | 875 | 593 (OB 294, YB 299) | 598 (OS 284, YS 314) | 99:100 | 104:100 | 95:100 |
| Control girls | 914 | 634 (OB 328, YB 306) | 642 (OS 302, YS 340) | 99:100 | 109:100 | 90:100 |
GD gender dysphoric, OB older brothers, YB younger brothers, OS older sisters, YS younger sisters
* p < .05, ** p < .001 for GD groups compared to the control groups per sex