Again you are wrong. There are two..a Yellowstone herd and one on a reservation that are pure bison, with no cattle genetics . And in other wild herds, there isn't enough to influence anything, just enough to show up in a DNA test, Kinda like DNA of most humans will show traces of Neanderthal . It would be impossible to isolate and "breed up" either to get a pure Cattle or a Neanderthal. There were white buffalo for hundreds of years in North America before cattle were brought over, Albinism is present in all mammals...bison are no different.