Sabino-1 causes white on the legs, belly and face, which often has roaning around the edges
Symbol
Sab1
Breeds known to carry this mutation
Many including Quarter Horses and related breeds, Paint Horses, and different types of ponies.
Inheritance pattern
Incomplete Dominance
Description
Sabino is an older term used to describe a number of spotting patterns. Sabino-1 is a specific mutation that causes white on the legs (often high) and belly, and a blaze. Extensive roaning is often evident, particularly at the edges of the white patterns. Homozygous horses (Sab1/Sab1) are almost completely, if not completely, white.
Interpretation of results
n/n: Horse does not carry the Sab1 mutation.
Sab1/n: Horse carries one copy of the Sab1 mutation and likely has high white stockings, a blaze, and it might have roaning or white on its belly.
Sab1/Sab1: Horse carries two copies of the Sab1 mutation. It is likely almost completely white and will pass the Sab1 mutation on to all its offspring.
Reference
Brooks & Bailey. Exon skipping in the KIT gene causes a Sabino spotting pattern in horses. Mammalian Genome 2005; 16:893-902. doi: 10.1007/s00335-005-2472-y