Muscular dystrophy-dystroglycanopathy / MDD (LARGE1-related) - Labrador Retriever

What does this test examine?

This genetic test examines the LARGE1 variant c.1363C>T in the Labrador Retriever. The test is used for muscular dystrophy-dystroglycanopathy / MDD. The condition is also known as LARGE1-related dystroglycanopathy, congenital muscular dystrophy-dystroglycanopathy and MDD.

What does this condition mean?

LARGE1 is required for proper glycosylation of alpha-dystroglycan, allowing muscle fibres to bind correctly to the extracellular matrix. The tested nonsense variant causes a severe dystroglycanopathy in Labrador Retrievers. Affected puppies show weakness, poor growth, bowed limbs, limited muscle development and often a very serious course.

Practical value of this test

This test helps Labrador breeders identify hidden carriers before matings are planned. Because affected puppies become severely ill, avoiding carrier-to-carrier matings is the main practical value of the test.

• Shows clearly whether a dog is clear, carries the tested variant or is genetically affected.
• Supports targeted breeding plans and helps avoid matings with an increased risk of affected puppies.
• Helps breeders manage carriers or positive animals responsibly without unnecessarily losing valuable lines.
• Gives owners and veterinarians concrete genetic information when muscle weakness, delayed growth, abnormal gait or muscle atrophy occurs in a line.

Result and inheritance

This condition is inherited in an autosomal recessive manner. A dog with C/C does not carry the variant. A dog with C/T is a carrier. A dog with T/T has the genotype that causes LARGE1-related muscular dystrophy-dystroglycanopathy.