Identification of a novel frameshift mutation in the DMD gene as the cause of muscular dystrophy in a Norfolk terrier dog.

BACKGROUND

A Norfolk terrier was referred to the Animal Health Trust neurology department with suspected dystrophin-deficient muscular dystrophy (DD-MD), which was confirmed by clinical workup and immunohistochemistry.

FINDINGS

Exon resequencing of the canine Duchenne Muscular Dystrophy (DMD) gene was undertaken to screen for potential disease causing mutations. The sequence data generated from all coding DMD exons revealed a 1 bp deletion in exon 22, causing a frameshift and premature termination of the coding sequence. Gene expression analysis indicated reduced levels of dystrophin transcript in the DD-MD case and western blot confirmed the absence of full length protein.

CONCLUSIONS

The finding represents a novel mutation causing DD-MD in the dog.