title: Familial clustering of muscular and cardiac involvement in myotonic dystrophy type 1.
abstract: Myotonic dystrophy type 1 (DM1) is associated with both skeletal and cardiac muscle involvement. The aim of the present study was to determine whether familial clustering is observed in the severity of muscle involvement in DM1. We evaluated 51 sibling groups constituting 112 patients with genetically-verified DM1. The siblings were similar to each other in age, cytosine-thymine-guanine (CTG) repeat length, age at disease onset, muscular impairment rating score, and electrocardiographic markers of cardiac conduction disease. After adjusting for the similarities between siblings in age and CTG repeat length, the siblings remained similar to each other in measures of both skeletal and cardiac muscle involvement. These results suggest that factors other than CTG repeat length play a role in the severity and progression of the degenerative skeletal and cardiac muscle disease in DM1.
authors.affiliation: Department of Medicine, Krannert Institute of Cardiology, Indiana University, 1800 North Capitol, Room E406, Indianapolis, Indiana 46202, USA. wgroh@iupui.edu
authors.forename: William J
authors.initials: WJ
authors.lastname: Groh
authors.forename: Miriam R
authors.initials: MR
authors.lastname: Lowe
authors.forename: Zachary
authors.initials: Z
authors.lastname: Simmons
authors.forename: Deepak
authors.initials: D
authors.lastname: Bhakta
authors.forename: Robert M
authors.initials: RM
authors.lastname: Pascuzzi
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D009202:Cardiomyopathies / Q000453:epidemiology / Q000235:genetics / Q000503:physiopathology*; D016000:Cluster Analysis; D018450:Disease Progression; D005260:Female; D005819:Genetic Markers / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006321:Heart / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology / Q000503:physiopathology*; D009206:Myocardium / Q000473:pathology*; D009223:Myotonic Dystrophy / Q000453:epidemiology / Q000235:genetics / Q000503:physiopathology*; D012042:Registries / Q000706:statistics & numerical data; D035781:Siblings; D018911:Trinucleotide Repeats / Q000235:genetics
chemical_list: D005819:Genetic Markers