Sarcoglycan A mutation in miniature dachshund dogs causes limb-girdle muscular dystrophy 2D.
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ABSTRACT: Background
A cohort of related miniature dachshund dogs with exercise intolerance, stiff gait, dysphagia, myoglobinuria, and markedly elevated serum creatine kinase activities were identified.Methods
Muscle biopsy histopathology, immunofluorescence microscopy, and western blotting were combined to identify the specific pathologic phenotype of the myopathy, and whole genome SNP array genotype data and whole genome sequencing were combined to determine its genetic basis.Results
Muscle biopsies were dystrophic. Sarcoglycanopathy, a form of limb-girdle muscular dystrophy, was suspected based on immunostaining and western blotting, where ?, ?, and ?-sarcoglycan were all absent or reduced. Genetic mapping and whole genome sequencing identified a premature stop codon mutation in the sarcoglycan A subunit gene (SGCA). Affected dachshunds were confirmed on several continents.Conclusions
This first SGCA mutation found in dogs adds to the literature of genetic bases of canine muscular dystrophies and their usefulness as comparative models of human disease.
SUBMITTER: Mickelson JR
PROVIDER: S-EPMC7789357 | biostudies-literature | 2021 Jan
REPOSITORIES: biostudies-literature
Publications
Sarcoglycan A mutation in miniature dachshund dogs causes limb-girdle muscular dystrophy 2D.
Mickelson James R JR Minor Katie M KM Guo Ling T LT Friedenberg Steven G SG Cullen Jonah N JN Ciavarella Amanda A Hambrook Lydia E LE Brenner Karen M KM Helmond Sarah E SE Marks Stanley L SL Shelton G Diane GD
Skeletal muscle 20210107 1
<h4>Background</h4>A cohort of related miniature dachshund dogs with exercise intolerance, stiff gait, dysphagia, myoglobinuria, and markedly elevated serum creatine kinase activities were identified.<h4>Methods</h4>Muscle biopsy histopathology, immunofluorescence microscopy, and western blotting were combined to identify the specific pathologic phenotype of the myopathy, and whole genome SNP array genotype data and whole genome sequencing were combined to determine its genetic basis.<h4>Results ...[more]
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