The merle gene has existed in the record of ADBA registered pet dogs, but breeders who applied the pet dogs for their historic ‘genetic endeavor’, identified there have been genetic flaws with pet dogs which have this colour sample. These canines were culled, instead of utilised as breeding stock. http://felixmgyqg.blogpostie.com/9039639/a-simple-key-for-merle-pitbull-puppies-for-sale-unveiled