Zebra seedling, zb4, has been located in chromosome 1 by the following studies.
| Genes | Phase | XY | Xy | xY | xy | Total | % Recomb. |
| Zb4 Br | RS | 448 | 142 | 152 | 12 | 754 | 31.1 |
| Zb4 F1 | RS | 455 | 135 | 158 | 9 | 757 | 28.0 |
| Zb4 Bm2 | RS | 487 | 103 | 144 | 23 | 757 | 46.0 |
| Zb4 P | CS | 266 | 24 | 5 | 64 | 359 | 6.9 |
Progeny of 1 ear indicated that the P parent was heterozygous giving the following segregation:
| CS | 63 | 30 | 2 | 24 | 199 | 6.7 |