Does anyone know anything about W20 color gene in Quarter Horses?

W20 is a dominant white gene. It enhances the white characteristics on a horse. By itself you may see white socks, a wide white blaze and maybe some random scattered belly spots. But in addition to another color gene, such as overo, tobiano or sabino, it is known to amplify or change the typical white markings. A horse with a pattern gene plus W20 will generally have more white or the white markings will be more jagged and extended. I believe the gene is common in reining horses.