| Designation | ISBT name | Cluster | Haplotype | Mechanism | Alterations | First mention | Definitive publication |
| CO(Q47R) | CO*01.-04 | main cluster | Colton | Single missense mutation | 140A>G (Q47R) | 2002 | 2010 |
| CO*02 | CO*02 CO*B | main cluster | Colton | Single missense mutation | 134C>T (A45V) | 1994 | 1994 |
| standard CO | C0*01.01 CO*A | main Cluster | Colton | standard sequence | 1991 | 1991 |