TTN-related myopathy, dominant-negative TTNsv

Definition

A skeletal muscle disorder caused by heterozygous multi-exon in-frame structural variants of TTN (TTNsv) that escape nonsense-mediated decay and result in expression of an internally deleted titin isoform with dominant-negative effects on sarcomere structure and function. Affected individuals typically present with congenital, childhood-onset, or adult-onset proximal and/or distal muscle weakness, often accompanied by joint contractures, and may develop respiratory involvement or cardiomyopathy.

Also known as TTN-related myopathy, dominant-negative TTNsv — per MONDO