| Designation | ISBT name | Cluster | Haplotype | Mechanism | Alterations | First mention | Definitive publication |
| Co(A45T) | main Cluster | Colton | Single missense mutation | 133G>A (A45T) | 2010 | 2010 | |
| CO*02 | CO*02 CO*B | main cluster | Colton | Single missense mutation | 134C>T (A45V) | 1994 | 1994 |