Muscular dystrophy (Duchenne type) - Cavalier King Charles Spaniel

General description

In the Cavalier King Charles Spaniel breed, a genetic variant was found in Exon 42 of the DMD (Duchenne muscular dystrophy) gene, which is associated with muscular dystrophy. Affected puppies are smaller than their siblings and cannot swallow and chew properly. At about 3 months of age, symptoms such as general muscle weakness, difficulty swallowing (dysphagia), increased saliva flow (ptyalism), nasal congestion, cough, fatigue and lethargy, enlarged tongue (macroglossia), excessive stretching of the carpal joints, a bonny-hopping gait and collapse after a few minutes of movement can be observed, too.

The variant in Exon 42 is located in a secondary hotspot for muscular dystrophy and is inherited in independently of the variant in intron 50, which is also occurring in this breed.