Dominant White (DW) is a dominant gene. It is also believed to be EMBRYONIC lethal in its homozygous form. Meaning the homozygous foal is never born and is aborted/absorbed by the mare early during the pregnancy, unlike Lethal White Overo, where the foal is born and will die shortly after birth.
There have now been at least 11 different Dominant White mutations found, and like they started with Sabino, all have a number i.e. DW 1, DW 2....DW 10, DW 11. Now despite the name "Dominant White" not all horses who are Dominant White are solid white. According to research most are at least 50% white.
The reason I am breaking from my pattern of going in order down the genes in my first post on this blog is because Dominant White is a new thing, and many horses previously thought to be Sabino are, in fact, Dominant white. Most notably is the Puchilingui line in Thoroughbreds.
Puchilingui himself was tested in the most recent Dominant White study, and was found to be positive for Dominant White
His son Sato, from Blazing Colours Farm, was also used in the study, and he was found to be positive for Dominant White as well.
This mare is Puchi Trap, from True Colours Farm. She is a daughter of Puchilingui, and while she was not used in the Dominant White study, based on her appearance, and her bloodlines, it is a very good bet that she is also Dominant White.
Another separate line of Dominant Whites, is the "Patchen" line. This first horse is Patchen Beauty, with her foal Patchen Prince running at her side.
This is an older photo of Patchen Prince running in a race
And here is another of Patchen Beautys foals, The White Fox. All three of these horses are confirmed Dominant White
This is Airdrie Apache. He has NOT been confirmed to be Dominant White, however his pattern, and his production record really lend credence to the theory that the Airdrie Apache line is Dominant White
This is a son of Airdri Apache named Allamystique from Reed Hill Farm
This mare is also from Reed Hill Farm, and is a daughter of Allamystique, and a grand daughter of Airdrie Apache