Cardiology
Session # 367
The TTN gene is expressed in striated muscle and encodes the protein titin, which spans half the distance of the sarcomere (from Z-disc to M-band) and is the largest known protein. Mutations in TTN constitute a substantial proportion of genetic risk for DCM, with mutation rates up to 25% in probands with familial dilated cardiomyopathy (DCM) and 18% in sporadic DCM cases. However, there is also a high burden of missense variants of unknown significance (VUS) detected in TTN. This makes the decision to choose a multigene panel (MGP) that includes TTN challenging when patients do not have a clear diagnosis of DCM. We sought to determine the characteristics and phenotypic spectrum associated with TTN pathogenic alterations, and to explore the decision to choose a panel including TTN for probands with cardiomyopathies.