| COLOR GENETICS | ||
| Allele | Description | Present In |
| B (BB, Bb) | Black v. Red | blacks, blues |
| b (bb) | Red (also responsible for sable/fawn in some breeds) | reds, fawns (isabellas) |
| D (DD, Dd) | Non-Dilution | blacks, reds |
| d (dd) | Dilution | blues, fawns (isabellas) |
|   | Black B_ | Red bb |
| Non-Dilute D_ | Black B_ D_ | Red bb D_ |
| Dilute dd | Blue B_ dd | Fawn (Isabella) bb dd |