The cream dilution gene can dilute both the red and black base colors and either have one copy of the cream gene (single dilution ) or two copies of the cream gene (double dilution). So the cream gene is the most common modifier giving us a variety of shades of coat colors. But there are some basics.
The red base color (chestnut) with a single dilution of cream yields a Palomino, and a double dilution produces a Cremello. There are no dorsal stripes or other black markings with a cream dilution of a chestnut.
The bay base color (black + the Agouti gene) with a single dilution yields a buckskin, and a double dilution produces a Perlino. Most buckskins do not have a prominent dorsal stripe unless they also have the dun gene.
A black horse without the Agouti gene and a single dilution of cream produces a Smokey Black, and a double dilution yield a Smoky Cream.
Horses that are Buckskin, Palomino or Smoky Black (single dilution) can pass the creme gene on to half of their foals. Double dilution horses (Cremello, Perlino and Smoky Cream) will always pass on at least one copy of the cream gene.
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