No, it is not. A breed comes from dogs that are genetically strong, and siring/producing their traits (note the plural, traits) when bred to outside stock. The resulting stock is often line-bred to affix traits, while consistently adding outside blood to maintain the overall health and integrity of the line and help eliminate undesirable traits as they crop up.
While it is true that line-breeding...and the occasional inbreeding...is often done, to consistently inbreed generation after generation to try and solidify a recessive trait....just that one color trait, to the exclusion of all other characteristics...results in all sorts of problems.

