title: S151A δ-sarcoglycan mutation causes a mild phenotype of cardiomyopathy in mice.
abstract: So far, the role of mutations in the δ-sarcogylcan (Sgcd) gene in causing autosomal dominant dilated cardiomyopathy (DCM) remains inconclusive. A p.S151A missense mutation in exon 6 of the Sgcd gene was reported to cause severe isolated autosomal dominant DCM without affecting skeletal muscle. This is controversial to our previous findings in a large consanguineous family where this p.S151A mutation showed no relevance for cardiac disease. In this study, the potential of the p.S151A mutation to cause DCM was investigated by using two different approaches: (1) engineering and characterization of heterozygous knock-in (S151A-) mice carrying the p.S151A mutation and (2) evaluation of the potential of adeno-associated virus (AAV) 9-based cardiac-specific transfer of p.S151A-mutated Sgcd cDNA to rescue the cardiac phenotype in Sgcd-deficient (Sgcd-null) mice as it has been demonstrated for intact, wild-type Sgcd cDNA. Heterozygous S151A knock-in mice developed a rather mild phenotype of cardiomyopathy. Increased heart to body weight suggests cardiac enlargement in 1-year-old S151A knock-in mice. However, at this age cardiac function, assessed by echocardiography, is maintained and histopathology completely absent. Myocardial expression of p.S151A cDNA, similar to intact Sgcd cDNA, restores cardiac function, although not being able to prevent myocardial histopathology in Sgcd-null mice completely. Our results suggest that the p.S151A mutation causes a mild, subclinical phenotype of cardiomyopathy, which is prone to be overseen in patients carrying such sequence variants. Furthermore, this study shows the suitability of an AAV-mediated cardiac gene transfer approach to analyze whether a sequence variant is a disease-causing mutation.
authors.affiliation: Department of Cardiology, Angiology and Pneumology, University Hospital, Heidelberg, Germany.
authors.forename: Désirée
authors.initials: D
authors.lastname: Rutschow
authors.affiliation: Department of Cardiology, Angiology and Pneumology, University Hospital, Heidelberg, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Bauer
authors.affiliation: Department of Cardiology, Angiology and Pneumology, University Hospital, Heidelberg, Germany.
authors.forename: Caroline
authors.initials: C
authors.lastname: Göhringer
authors.affiliation: Department of Cardiology, Angiology and Pneumology, University Hospital, Heidelberg, Germany.
authors.forename: Raffi
authors.initials: R
authors.lastname: Bekeredjian
authors.affiliation: Department of Cardiology, Angiology and Pneumology, University Hospital, Heidelberg, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Schinkel
authors.affiliation: Institute of Human Genetics, Newcastle University, International Centre for Life, Newcastle upon Tyne, UK.
authors.forename: Volker
authors.initials: V
authors.lastname: Straub
authors.affiliation: Max-Planck Institute for Medical Research, Heidelberg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Koenen
authors.affiliation: Division of Epigenomics and Cancer Risk Factors, German Cancer Research Centre, Heidelberg, Germany.
authors.forename: Dieter
authors.initials: D
authors.lastname: Weichenhan
authors.affiliation: 1] Department of Cardiology, Angiology and Pneumology, University Hospital, Heidelberg, Germany [2] DZHK (German Centre for Cardiovascular Research), partner site Heidelberg, Heidelberg, Germany.
authors.forename: Hugo A
authors.initials: HA
authors.lastname: Katus
authors.affiliation: 1] Department of Cardiology, Angiology and Pneumology, University Hospital, Heidelberg, Germany [2] DZHK (German Centre for Cardiovascular Research), partner site Heidelberg, Heidelberg, Germany.
authors.forename: Oliver J
authors.initials: OJ
authors.lastname: Müller
mesh_terms: D000818:Animals; D009202:Cardiomyopathies / Q000209:etiology / Q000235:genetics* / Q000473:pathology; D000229:Dependovirus; D055879:Gene Knock-In Techniques; D006579:Heterozygote; D006801:Humans; D051379:Mice; D020125:Mutation, Missense; D009206:Myocardium / Q000473:pathology; D010641:Phenotype; D049031:Sarcoglycans / Q000235:genetics*
chemical_list: D049031:Sarcoglycans