Merle Breeding Safety
Understanding merle genetics is not optional for breeders - it is a fundamental responsibility. This resource provides the scientific knowledge and practical protocols to produce beautiful merle dogs without creating preventable suffering.
Merle-to-merle breeding produces a 25% chance of double merle (MM) puppies. These dogs frequently suffer from severe eye abnormalities, deafness, and other health issues. This is entirely preventable through proper genetic testing.
Essential Reading
The Merle Gene: Beautiful and Dangerous
Understanding the genetics behind the stunning merle pattern and why it demands respect from every breeder.
Double Merle: The Heartbreak of MM Puppies
The devastating reality of homozygous merle puppies. Blindness, deafness, and a lifetime of challenges.
Cryptic Merle: The Hidden Danger in Your Lines
Why visual inspection fails and how invisible merle carriers are producing affected puppies worldwide.
Testing Before Breeding: Available Tests and Labs
A comprehensive guide to genetic testing options, laboratories, and interpreting your dog's merle status.
Responsible Merle Breeding: How to Do It Right
Protocols, pairings, and practices that preserve the beautiful pattern while protecting puppy welfare.
Advanced Topics
The SILV/PMEL17 Gene: Understanding Merle at the Molecular Level
Deep dive into the molecular genetics of the merle pattern. SINE insertions, poly-A tail instability, and the science behind safe breeding.
Health Issues in Double Merle Dogs: A Comprehensive Medical Guide
Detailed veterinary guide to ocular abnormalities, deafness, dermatological issues, and quality of life in MM dogs.
Breed-Specific Merle Guidelines: Standards and Registrations
Traditional merle breeds versus non-standard introductions. Kennel club policies and breed-specific considerations.
Ethical Considerations in Merle Breeding
Examining breeder responsibility, animal welfare principles, and the moral dimensions of merle breeding decisions.
Harlequin and Merle Interaction in Great Danes
The complex interaction between harlequin and merle genes. Safe breeding combinations and the embryonic lethal factor.
Merle Allele Instability: Why Offspring May Differ from Parents
Understanding poly-A tail instability and why individual DNA testing is essential for every breeding dog.
Puppy Buyer's Guide: What to Know Before Purchasing a Merle Dog
Essential guide for prospective buyers. Questions to ask breeders, documentation to request, and red flags to watch for.
Merle and Coat Colour Interactions: What Base Colours Reveal
How merle interacts with sable, recessive red, and dilution. Understanding hidden merle risks in different coat colours.
With proper genetic testing and responsible breeding practices, you can produce beautiful merle puppies without ever creating a double merle. Every article on this site is designed to give you the knowledge to breed safely and ethically.
Dr. Patricia Wells
Canine Coat Genetics Specialist
Veterinary geneticist with over 25 years researching coat colour inheritance in domestic canids. Former research fellow at the Animal Health Trust and consultant to multiple breed health programmes across Europe and North America. Dedicated to translating complex genetic science into practical guidance for responsible breeders.
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