| Superfamily | Description | Architecture | Class | n° Families | Structures |
|---|---|---|---|---|---|
| Intron_gpII | Superfamily of Intron_gpII | Intron_gpII-like | structured_complex | 5 | |
| U2 | Superfamily of U2 | Intron_gpII-like | structured_complex | 3 | |
| U5 | Superfamily of U5 | Intron_gpII-like | structured_complex | 1 | |
| U6 | Superfamily of U6 | Intron_gpII-like | structured_complex | 3 |