Blue roan can be applied to any roan with a dark underlying coat that gives it a bluish cast. But this roan is dominantly a synonym for a roan with a black background coat.
Many horse breeds carry this roan gene. Popular equine breeds without this roan are Thoroughbreds and Arabians. They have horses with grey color patterns that resemble roans, however, they are not genetically roan.
BLUE ROAN FACTS
There are a few Thoroughbreds that look similar, but genetically, they are different. It’s difficult to comprehend the distinction, but by thinking about human genetics, it becomes clear.
Draft horse breeds, pony breeds, and also many equine breeds originating in North America possess the roan gene. These include the American Quarter horse, Percheron, Belgian, Welsh piny, American Paint Horse, and also Paso Fino.