How is myotonia congenita inherited in dogs?

Myotonia congenita is autosomal recessive, caused by a CLCN1 gene mutation. It affects Australian Cattle Dogs and Border Collies. Affected dogs have two copies, carriers have one (clinically normal), clear dogs have none. DNA testing is definitive. Never breed two carriers — Carrier × Clear pairings produce no affected puppies. Test all breeding stock and share results with breed clubs. Transparency with puppy buyers about parent testing status is important. Our vets can help interpret results and plan safe pairings.