Congenital stationary night blindness (CSNB) is the inability to see in low to no-light conditions (essentially dusk to dawn). It is found in horses with two copies of a specific white spotting pattern mutation known as leopard complex spotting (LP), which is characterized by a symmetrical white pattern centered over the rump with few or no spots of pigment in this white patterned area. This coat pattern is common in Appaloosas, Miniature Horses, Knabstruppers, Norikers, and some other breeds.