The dun dilution gene is best described as revealing "primitive" markings. It dilutes both red and black pigment selectively, leaving certain areas and patterns in their original color. The dun's primitive markings are: dorsal stripe, leg barring, shoulder stripe, ear barring, forehead spider-webbing, and a face mask.
While each dun horse may have a different combination of primitive markings, all dun horses have the dorsal stripe and some leg barring. The dorsal stripe is a dark stripe that runs along the horse's spine, and the leg barring refers to zebra-like stripes on the horse's legs.
Since the dun gene affects both red and black pigment, it can create three basic types of dun: the red dun, classic dun, and grullo.Previous: Cream Dilution - Home - Next: Champagne