Sabino is a term used to describe a group of similar white spotting irregular patterns on the skin and hair of the legs, belly and face, often with roaning around the edges.
Sabino horses are described to have belly spots, irregular face markings that often extends past the eyes or onto the chin, white markings above the knees or hocks, and "splash" or "lacy" marks anywhere on the body, but in particular on the belly. Some Sabinos have patches of roan patterning on part of the body, particularly on the barrel and flanks. Some Sabinos may have a dark foot or two, but most have four white feet. Both blue and brown eyes are seen.
There is a number of mutations that produce the Sabino pattern, Sabino 1 (SB1) is one of these mutations that has been identified. Horses carrying this mutation are Sabinos, however not all Sabino horses carry this mutation, there are still unidentified mutations that produce the Sabino pattern.
The mode of inheritance is autosomal dominant, which means that only one copy of the Sabino 1 mutation is enough to produce a Sabino pattern. When one copy of the Sabino 1 mutation is present (N / SB1) the horse is expected to have two or more white legs or feet, often with white marking on the front of the leg, an extensive blaze, white spotting on the midsection with roaned or jagged edges. Horses with two copies of the mutation (SB1/SB1) are almost completely white with pink or partially-pigmented skin, they are described as Sabino-White.