TTN and familial dilated cardiomyopathy: As in adult-onset cardiomyopathy, genetic testing has now been integrated into daily clinical practice in the pediatric population, and a genetic cause can be identified in up to 27%–54% of pediatric DCM patients.7–9myosin heavy chain 7 (MYH7) (5.1%), vinculin (VCL) (3.2%), and tropomyosin1 (TPM1) (2.2%) are among the most frequently affected genes in children younger than 2 years of age, whereas titin (TTN) (10.0%), RNA-binding motif 20 (RBM20) (6.7%), and troponin T2 (TNNT2) (4.7%) are the most frequently mutated genes in the 2–18 year age group.10