Final Point: It is unrealistic to expect any dog population to be free of genetic diseases but many breeders of every type have intentionally selected for traits that result in diseases and this is shameful. If “improvement” in looks imposes a health burden then it is not a breed improvement.
No dog breed has ever been improved by the capricious and arbitrary decision that a /shorter/longer/flatter/bigger/smaller/curlier/ “whatever or color” is better. Condemning a dog or a breed to a lifetime of suffering for the sake of looks is not an improvement; it is torture. The Merle pattern is not an improvement to health, therefore should not be added.
Ask yourself: Why is the Merle pattern banned in so many countries if there is nothing to be concerned about? We can infer based on the evidence this mutated gene is an unethical trait to breed into a dog because of the health issues. The mutated gene is in some cases lethal and not worth the risk. Not to mention it can be hidden and hard to rule out in the coat color. Put living creatures before a fad.
BREEDERS: Now that you are informed. Let's infer the Merle pattern is unethical to add into your breeding program because of the mutated gene. Please think about the future of the breed and families who rely on you to be honest, ethical, and committed to the breeds health. Do not convince yourself that you are just doing what was done with new breeds in the past. There is a GOOD reason merle is banned in many countries. It is LETHAL to the health of the breed. If you do proceed you owe your buyers health CERF on eyes at the very least and BAER testing for hearing.
BUYERS: Please do not get swept off your feet by the Merle pattern or any BLUE EYED Schnauzers. Sadly, what makes the Merle pattern so unique also makes it quite lethal and risky. The blue eyed AKC Miniature Schnauzers are being 'marketed' as AKC registered. However, until recently Miniature Schnauzer NEVER had blue eyes. The same breeders who bred the Merle pattern (which carries for blue and partial blue eyes) are the first to offer this NEW trait being introduced to purebred Miniature Schnauzers and it is a startling coincidence considering Merle patterns also produce blue eyes, one blue eye, or partial blue eyes. IF YOU BUY A MERLE OR A BLUE EYED 'MINIATURE SCHNAUZER' YOU ARE SUPPORTING A FAD THAT IS UNHEALTHY TO THIS BREED.
The AKC does not regulate eye color or request proof of parentage unless someone submits a complaint which cost $500 to pursue. A DNA test for a dog will only confirm a genetic match if its parents have also been DNA tested AND they swabbed the right dog. The AKC does not stand in the breeders house and watch what dog is being swabbed. They trust the breeder is swabbing with honesty. The DNA certification from the AKC has nothing to do with defining a purebred from a mutt or ruling out cross breeding. It is a tool the AKC implemented to track sires of a litter and in some cases dams. LINK: http://www.akc.org/dna/certify.cfm
FYI: If you buy an AKC Merle Miniature Schnauzer then you need to call the AKC and report the breeder. This is NOT a color pattern option for this breed and the papers have been obtained under false information. CONTACT: https://www.akc.org/telephone-directory/
NOTE: Merle Schnauzers are a mixed breed and NOT purebred. They are NOT recognized by any of the well-established kennel clubs such the AKC or FCI. The dog registry for Merles was created for the purpose of selling 'registered' puppies. The acronym used for this Merle 'dog registry' happens to be MSCA, which is almost the same acronym as the Miniature Schnauzer Club of America (AMSC) HOWEVER they are NOT affiliated.