what is its relation to sabino?
It is a group of white spotting patterns in horses that affect the skin and hair.
Sabino horse
Sabino is a group of white spotting patterns in horses that affect the skin and hair.
what is dominant white? A.k.a  white spotting -  group of genetically related coat color conditions in the horse, best known for producing an all-white coat. how is this identifed? UNANSWERABLE
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Sabino horse [SEP] Introduction
Sabino is a group of white spotting patterns in horses that affect the skin and hair. A wide variety of irregular color patterns are accepted as sabino. In the strictest sense, "sabino" refers to the white patterns produced by the "Sabino 1" (SB1) gene, for which there is a DNA test. However, other horse enthusiasts also refer to patterns that are visually similar to SB1 as "sabino", even if testing indicates the gene is not present. Use of the term to describe non-SB1 "sabino" patterns in breeds that apparently do not carry the gene is hotly debated by both researchers and horse breeders.