The protein melanophilin (MLPH gene) is responsible for the dilute coat colour.

 This variation causes black, brown and yellow hair (eumelanin or phaeomelanin pigments) to be diluted.

 Referred to as blue, charcoal, grey and in cobination with other colours lilac or champagne.

 A normal result is usually reported as DD (no copies of dilute), with carrier as Dd (one copy of the dilute) and a dilute colour dog affected is reported dd.