A disorder of the musculoskeletal system caused by pathogenic variants in the TTN gene encoding the titin protein expressed in striated muscle. These variants are associated with a variety of overlapping congenital and adult-onset myopathies characterized by non-progressive or progressive neck, axial, and limb weakness, joint contractures, early-onset respiratory insufficiency, facial weakness, congenital cardiac anomalies and/or early-onset dilated cardiomyopathy. Histologic findings on skeletal muscle biopsy reveal a wide range of structural abnormalities and can include increased internalized and central nuclei, minicores, and dystrophic changes. [ https://clinicalgenome.org/affiliation/40031/ http://www.ncbi.nlm.nih.gov/pubmed/27854229 http://www.ncbi.nlm.nih.gov/pubmed/29691892 ]
Synonyms: TTN myopathy TTN-related myopathy congenital myopathy related to TTN
Term information
rare, inferred_rare, clingen
In the absence of evidence supporting distinct differences in molecular mechanisms between the associated disease entities, as well as considerable phenotypic overlap, these entities can be considered part of a clinical spectrum of TTN-related myopathy.