What is a Biewer Yorkie? Basically, it is a Yorkie of German heritage in which two recessive genes produced the first full tri-colored Yorkie. The same thing also happened here in the U.S. and those are called AKC Parti-Yorkies. When you breed an American Yorkie with a full tri-colored Biewer, they produce what is called F1's. If you breed the F1 to a full tri-colored yorkie, you get F2's. See the breeding chart on Our Biewers page for more information concerning breeding.