The physical appearance of this domestic cat breed barely changed when compared to photos dating back to the late 1800s. However, since some breeders in the United States and other parts of the world introduced the brachycephalic mutation into the breed, the short nose and clear break became shorter and higher. This resulted in the modification of the original Persian breed standard so that modern show quality Persians must have peke-faces. This resulted in the breed disappearing from cat shows.