Join Date: Aug 2010
Location: Perth, Western Australia
• Horses: 0
Yes, any sort of white has to be caused by a pattern gene of some description (except white caused by scarring of the skin, either through injury or fungus etc.). Off the top of my head there are the following white patterns: Tobiano, sabino, splash, frame, rabicano, dominant white (11 different varieties, maybe 12, so far), classic roan, appaloosa (5 different ways) and grey. Then you can also have Birdcatcher spots, which may be genetic but it is difficult to determine as yet.
If a tobiano has face white, yes, there has to be another white patterning gene present. The three that cause face white are splash, sabino and frame.