Tobiano
Tobiano spotting is characterized by large white patches on the limbs and body. Oftentimes, these patches have smooth edges, cross over the topline, and are accompanied by dark eyes. Expression can range from white present only on the legs, to horses nearly completely white. As this trait is dominant, horses with either one (TO/N) or two (TO/TO) copies will have a similar appearance.
Frame Overo
Frame overo (lethal white overo) is a white spotting pattern characterized by patches of white-bordered or “framed” by normal pigmentation. It is usually accompanied by blue eyes, and generally, white patterning does not cross the topline. While heterozygous horses (LWO/N) only have this white spotting pattern, homozygous foals (LWO/LWO) are born completely white and with megacolon, an abnormal dilation of the colon that necessitates immediate euthanasia.
Sabino 1
Sabino spotting is characterized by extended white markings on the legs and face, often accompanied by a belly spot and roaning throughout the coat. Unlike other white patterns, sabino horses usually have dark-coloured eyes. Horses with a single copy of sabino-1 (SB1/N) display this characteristic pattern, whereas horses that have inherited two copies (SB1/SB1) are almost completely white.
Dominant White W5, 10, 20, 22, 31, 32, 34, 35
Dominant white (“W”) refers to a class of white spotting patterns in which a horse with one copy generally displays markings on 50-100% of the body. Unlike other extreme white patterns, this trait generally leaves the eyes dark.
Splash White 1, 2, 3, 5, 6, 7
Splash White is a white spotting pattern characterized by large amounts of white on the legs, face, and sometimes tail/belly, giving a horse the appearance of being dipped in paint. Oftentimes, splashed white horses have one or two blue eyes, and may be deaf. SW1 is incompletely dominant, with heterozygotes (SW1/N) displaying "typical" white markings and homozygotes (SW1/SW1) having a classic splashed white appearance. Horses with one copy of any of the other splashed whites (SW2, SW3, SW4, SW5, SW6, SW7, SW8, SW9, SW10) likely have the typical splashed white appearance. On rare occasions, splashed white may be hidden (not expressed in the phenotype).
